/*      $NetBSD: fd.c,v 1.129 2024/01/07 07:58:33 isaki 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 and Minoura Makoto.
 *
 * 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 1.129 2024/01/07 07:58:33 isaki Exp $");

#include "opt_ddb.h"
#include "opt_m68k_arch.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/callout.h>
#include <sys/kernel.h>
#include <sys/conf.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/malloc.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 <sys/proc.h>
#include <sys/fdio.h>
#include <sys/rndsource.h>

#include <dev/cons.h>

#include <machine/cpu.h>

#include <arch/x68k/dev/intiovar.h>
#include <arch/x68k/dev/dmacvar.h>
#include <arch/x68k/dev/fdreg.h>
#include <arch/x68k/dev/opmvar.h> /* for CT1 access */

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

#ifdef FDDEBUG
#define DPRINTF(x)      if (fddebug) printf x
int     fddebug = 0;
#else
#define DPRINTF(x)
#endif

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

/* (mis)use device use flag to identify format operation */
#define B_FORMAT B_DEVPRIVATE

enum fdc_state {
        DEVIDLE = 0,
        MOTORWAIT,
        DOSEEK,
        SEEKWAIT,
        SEEKTIMEDOUT,
        SEEKCOMPLETE,
        DOIO,
        IOCOMPLETE,
        IOTIMEDOUT,
        DORESET,
        RESETCOMPLETE,
        RESETTIMEDOUT,
        DORECAL,
        RECALWAIT,
        RECALTIMEDOUT,
        RECALCOMPLETE,
        DOCOPY,
        DOIOHALF,
        COPYCOMPLETE,
};

/* software state, per controller */
struct fdc_softc {
        bus_space_tag_t sc_iot;         /* intio i/o space identifier */
        bus_space_handle_t sc_ioh;      /* intio io handle */

        struct callout sc_timo_ch;      /* timeout callout */
        struct callout sc_intr_ch;      /* pseudo-intr callout */

        bus_dma_tag_t sc_dmat;          /* intio DMA tag */
        bus_dmamap_t sc_dmamap;         /* DMA map */
        uint8_t *sc_addr;               /* physical address */
        struct dmac_channel_stat *sc_dmachan; /* intio DMA channel */
        struct dmac_dma_xfer *sc_xfer;  /* DMA transfer */
        int sc_read;

        struct fd_softc *sc_fd[4];      /* pointers to children */
        TAILQ_HEAD(drivehead, fd_softc) sc_drives;
        enum fdc_state sc_state;
        int sc_errors;                  /* number of retries so far */
        uint8_t sc_status[7];           /* copy of registers */
};

static int fdcintr(void *);
static void fdcreset(struct fdc_softc *);

/* controller driver configuration */
static int fdcprobe(device_t, cfdata_t, void *);
static void fdcattach(device_t, device_t, void *);
static int fdprint(void *, const char *);

CFATTACH_DECL_NEW(fdc, sizeof(struct fdc_softc),
    fdcprobe, fdcattach, NULL, NULL);

/*
 * 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 */
        uint8_t fillbyte;       /* format fill byte */
        uint8_t interleave;     /* interleave factor (formatting) */
        const char *name;
};

/* The order of entries in the following table is important -- BEWARE! */
static struct fd_type fd_types[] = {
        {  8,2,16,3,0xff,0xdf,0x35,0x74,77,1232,1,FDC_500KBPS, 0xf6, 1,
            "1.2MB/[1024bytes/sector]"    }, /* 1.2 MB japanese format */
        { 18,2,36,2,0xff,0xcf,0x1b,0x6c,80,2880,1,FDC_500KBPS, 0xf6, 1,
            "1.44MB"    }, /* 1.44MB diskette */
        { 15,2,30,2,0xff,0xdf,0x1b,0x54,80,2400,1,FDC_500KBPS, 0xf6, 1,
            "1.2MB"    }, /* 1.2 MB AT-diskettes */
        {  9,2,18,2,0xff,0xdf,0x23,0x50,40, 720,2,FDC_300KBPS, 0xf6, 1,
            "360KB/AT" }, /* 360kB in 1.2MB drive */
        {  9,2,18,2,0xff,0xdf,0x2a,0x50,40, 720,1,FDC_250KBPS, 0xf6, 1,
            "360KB/PC" }, /* 360kB PC diskettes */
        {  9,2,18,2,0xff,0xdf,0x2a,0x50,80,1440,1,FDC_250KBPS, 0xf6, 1,
            "720KB"    }, /* 3.5" 720kB diskette */
        {  9,2,18,2,0xff,0xdf,0x23,0x50,80,1440,1,FDC_300KBPS, 0xf6, 1,
            "720KB/x"  }, /* 720kB in 1.2MB drive */
        {  9,2,18,2,0xff,0xdf,0x2a,0x50,40, 720,2,FDC_250KBPS, 0xf6, 1,
            "360KB/x"  }, /* 360kB in 720kB drive */
};

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

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

#if 0   /* see comments in fd_motor_on() */
        struct callout sc_motoron_ch;
#endif
        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_BOPEN        0x01            /* it's open */
#define FD_COPEN        0x02            /* it's open */
#define FD_OPEN         (FD_BOPEN|FD_COPEN)     /* it's open */
#define FD_MOTOR        0x04            /* motor should be on */
#define FD_MOTOR_WAIT   0x08            /* motor coming up */
#define FD_ALIVE        0x10            /* alive */
        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 */
        uint8_t *sc_copybuf;    /* for secsize >=3 */
        uint8_t sc_part;        /* for secsize >=3 */
#define SEC_P10 0x02            /* first part */
#define SEC_P01 0x01            /* second part */
#define SEC_P11 0x03            /* both part */

        krndsource_t    rnd_source;
};

/* 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);

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

const struct bdevsw fd_bdevsw = {
        .d_open = fdopen,
        .d_close = fdclose,
        .d_strategy = fdstrategy,
        .d_ioctl = fdioctl,
        .d_dump = nodump,
        .d_psize = nosize,
        .d_discard = nodiscard,
        .d_flag = D_DISK
};

const struct cdevsw fd_cdevsw = {
        .d_open = fdopen,
        .d_close = fdclose,
        .d_read = fdread,
        .d_write = fdwrite,
        .d_ioctl = fdioctl,
        .d_stop = nostop,
        .d_tty = notty,
        .d_poll = nopoll,
        .d_mmap = nommap,
        .d_kqfilter = nokqfilter,
        .d_discard = nodiscard,
        .d_flag = D_DISK
};

static void fdstart(struct fd_softc *);

struct dkdriver fddkdriver = {
        .d_strategy = fdstrategy
};

static void fd_set_motor(struct fdc_softc *, int);
static void fd_motor_off(void *);
#if 0
static void fd_motor_on(void *);
#endif
static int fdcresult(struct fdc_softc *);
static int out_fdc(bus_space_tag_t, bus_space_handle_t, uint8_t);
static void fdcstart(struct fdc_softc *);
static void fdcstatus(device_t, int, const char *);
static void fdctimeout(void *);
#if 0
static void fdcpseudointr(void *);
#endif
static void fdcretry(struct fdc_softc *);
static void fdfinish(struct fd_softc *, struct buf *);
static struct fd_type *fd_dev_to_type(struct fd_softc *, dev_t);
static int fdformat(dev_t, struct ne7_fd_formb *, struct lwp *);
static int fdcpoll(struct fdc_softc *);
static int fdgetdisklabel(struct fd_softc *, dev_t);
static void fd_do_eject(struct fdc_softc *, int);

static void fd_mountroot_hook(device_t);

/* DMA transfer routines */
inline static void fdc_dmastart(struct fdc_softc *, int, void *, vsize_t);
inline static void fdc_dmaabort(struct fdc_softc *);
static int fdcdmaintr(void *);
static int fdcdmaerrintr(void *);

inline static void
fdc_dmastart(struct fdc_softc *fdc, int read, void *addr, vsize_t count)
{
        int error;

        DPRINTF(("fdc_dmastart: %s, addr = %p, count = %ld\n",
            read ? "read" : "write", (void *)addr, count));

        error = bus_dmamap_load(fdc->sc_dmat, fdc->sc_dmamap, addr, count,
            0, BUS_DMA_NOWAIT);
        if (error) {
                panic("fdc_dmastart: cannot load dmamap");
        }

        bus_dmamap_sync(fdc->sc_dmat, fdc->sc_dmamap, 0, count,
            read ? BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);

        /*
         * Note 1:
         *  uPD72065 ignores A0 input (connected to x68k bus A1)
         *  during DMA xfer access, but it's better to explicitly
         *  specify FDC data register address for clarification.
         * Note 2:
         *  FDC is connected to LSB 8 bits of X68000 16 bit bus
         *  (as BUS_SPACE_MAP_SHIFTED_ODD defined in bus.h)
         *  so each FDC register is mapped at sparse odd address.
         *
         * XXX: No proper API to get DMA address of FDC register for DMAC.
         */
        fdc->sc_xfer = dmac_prepare_xfer(fdc->sc_dmachan, fdc->sc_dmat,
            fdc->sc_dmamap,
            read ? DMAC_OCR_DIR_DTM : DMAC_OCR_DIR_MTD,
            DMAC_SCR_MAC_COUNT_UP | DMAC_SCR_DAC_NO_COUNT,
            fdc->sc_addr + fddata * 2 + 1);

        fdc->sc_read = read;
        dmac_start_xfer(fdc->sc_dmachan->ch_softc, fdc->sc_xfer);
}

inline static void
fdc_dmaabort(struct fdc_softc *fdc)
{

        dmac_abort_xfer(fdc->sc_dmachan->ch_softc, fdc->sc_xfer);
        bus_dmamap_unload(fdc->sc_dmat, fdc->sc_dmamap);
}

static int
fdcdmaintr(void *arg)
{
        struct fdc_softc *fdc = arg;

        bus_dmamap_sync(fdc->sc_dmat, fdc->sc_dmamap,
            0, fdc->sc_dmamap->dm_mapsize,
            fdc->sc_read ?
            BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
        bus_dmamap_unload(fdc->sc_dmat, fdc->sc_dmamap);

        return 0;
}

static int
fdcdmaerrintr(void *dummy)
{

        DPRINTF(("fdcdmaerrintr\n"));

        return 0;
}

/* ARGSUSED */
static int
fdcprobe(device_t parent, cfdata_t cf, void *aux)
{
        struct intio_attach_args *ia = aux;

        if (strcmp(ia->ia_name, "fdc") != 0)
                return 0;

        if (ia->ia_addr == INTIOCF_ADDR_DEFAULT)
                ia->ia_addr = FDC_ADDR;
        if (ia->ia_intr == INTIOCF_INTR_DEFAULT)
                ia->ia_intr = FDC_INTR;
        if (ia->ia_dma == INTIOCF_DMA_DEFAULT)
                ia->ia_dma = FDC_DMA;
        if (ia->ia_dmaintr == INTIOCF_DMAINTR_DEFAULT)
                ia->ia_dmaintr = FDC_DMAINTR;

        if ((ia->ia_intr & 0x03) != 0)
                return 0;

        ia->ia_size = FDC_MAPSIZE;
        if (intio_map_allocate_region(parent, ia, INTIO_MAP_TESTONLY))
                return 0;

        /* builtin device; always there */
        return 1;
}

/*
 * 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.
 */
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;
}

static void
fdcattach(device_t parent, device_t self, void *aux)
{
        struct fdc_softc *fdc = device_private(self);
        bus_space_tag_t iot;
        bus_space_handle_t ioh;
        struct intio_attach_args *ia = aux;
        struct fdc_attach_args fa;

        iot = ia->ia_bst;

        aprint_normal("\n");

        /* Re-map the I/O space. */
        if (bus_space_map(iot, ia->ia_addr, ia->ia_size,
            BUS_SPACE_MAP_SHIFTED_ODD, &ioh) != 0) {
                aprint_error_dev(self, "unable to map I/O space\n");
                return;
        }

        callout_init(&fdc->sc_timo_ch, 0);
        callout_init(&fdc->sc_intr_ch, 0);

        fdc->sc_iot = iot;
        fdc->sc_ioh = ioh;
        fdc->sc_addr = (void *)ia->ia_addr;

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

        /* Initialize DMAC channel */
        fdc->sc_dmachan = dmac_alloc_channel(parent, ia->ia_dma, "fdc",
            ia->ia_dmaintr, fdcdmaintr, fdc,
            ia->ia_dmaintr + 1, fdcdmaerrintr, fdc,
            (DMAC_DCR_XRM_CSWH | DMAC_DCR_OTYP_EASYNC | DMAC_DCR_OPS_8BIT),
            (DMAC_OCR_SIZE_BYTE | DMAC_OCR_REQG_EXTERNAL));

        if (bus_dmamap_create(fdc->sc_dmat, FDC_MAXIOSIZE, 1, DMAC_MAXSEGSZ,
            0, BUS_DMA_NOWAIT | BUS_DMA_ALLOCNOW, &fdc->sc_dmamap)) {
                aprint_error_dev(self, "can't set up intio DMA map\n");
                return;
        }

        if (intio_intr_establish(ia->ia_intr, "fdc", fdcintr, fdc) != 0)
                panic("Could not establish interrupt (duplicated vector?).");
        intio_set_ivec(ia->ia_intr);

        /* reset */
        intio_disable_intr(SICILIAN_INTR_FDD);
        intio_enable_intr(SICILIAN_INTR_FDC);
        fdcresult(fdc);
        fdcreset(fdc);

        aprint_normal_dev(self, "uPD72065 FDC\n");
        out_fdc(iot, ioh, NE7CMD_SPECIFY);      /* specify command */
        out_fdc(iot, ioh, 0xd0);
        out_fdc(iot, ioh, 0x10);

        /* physical limit: four drives per controller. */
        for (fa.fa_drive = 0; fa.fa_drive < 4; fa.fa_drive++) {
                (void)config_found(self, (void *)&fa, fdprint, CFARGS_NONE);
        }

        intio_enable_intr(SICILIAN_INTR_FDC);
}

static void
fdcreset(struct fdc_softc *fdc)
{

        bus_space_write_1(fdc->sc_iot, fdc->sc_ioh, fdsts, NE7CMD_RESET);
}

static int
fdcpoll(struct fdc_softc *fdc)
{
        int i = 25000;

        while (--i > 0) {
                if ((intio_get_sicilian_intr() & SICILIAN_STAT_FDC) != 0) {
                        out_fdc(fdc->sc_iot, fdc->sc_ioh, NE7CMD_SENSEI);
                        fdcresult(fdc);
                        break;
                }
                DELAY(100);
        }
        return i;
}

static int
fdprobe(device_t parent, cfdata_t cf, void *aux)
{
        struct fdc_softc *fdc = device_private(parent);
        struct fd_type *type;
        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 = 0;
        int found = 0;
        int i;

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

        type = &fd_types[0];    /* XXX 1.2MB */

        /* toss any interrupt status */
        for (n = 0; n < 4; n++) {
                out_fdc(iot, ioh, NE7CMD_SENSEI);
                (void)fdcresult(fdc);
        }
        intio_disable_intr(SICILIAN_INTR_FDC);

        /* select drive and turn on motor */
        bus_space_write_1(iot, ioh, fdctl, 0x80 | (type->rate << 4)| drive);
        fdc_force_ready(FDCRDY);
        fdcpoll(fdc);

 retry:
        out_fdc(iot, ioh, NE7CMD_RECAL);
        out_fdc(iot, ioh, drive);

        i = 25000;
        while (--i > 0) {
                if ((intio_get_sicilian_intr() & SICILIAN_STAT_FDC) != 0) {
                        out_fdc(iot, ioh, NE7CMD_SENSEI);
                        n = fdcresult(fdc);
                        break;
                }
                DELAY(100);
        }

#ifdef FDDEBUG
        {
                int _i;
                DPRINTF(("fdprobe: status"));
                for (_i = 0; _i < n; _i++)
                        DPRINTF((" %x", fdc->sc_status[_i]));
                DPRINTF(("\n"));
        }
#endif

        if (n == 2) {
                if ((fdc->sc_status[0] & 0xf0) == 0x20)
                        found = 1;
                else if ((fdc->sc_status[0] & 0xf0) == 0xc0)
                        goto retry;
        }

        /* turn off motor */
        bus_space_write_1(fdc->sc_iot, fdc->sc_ioh,
            fdctl, (type->rate << 4) | drive);
        fdc_force_ready(FDCSTBY);
        if (!found) {
                intio_enable_intr(SICILIAN_INTR_FDC);
                return 0;
        }

        return 1;
}

/*
 * Controller is working, and drive responded.  Attach it.
 */
static 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;
        struct fd_type *type = &fd_types[0];    /* XXX 1.2MB */
        int drive = fa->fa_drive;

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

        fd->sc_dev = self;
        fd->sc_flags = 0;

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

        fd->sc_copybuf = malloc(PAGE_SIZE, M_DEVBUF, M_WAITOK);
        if (fd->sc_copybuf == 0)
                aprint_error("%s: WARNING!! malloc() failed.\n", __func__);
        fd->sc_flags |= FD_ALIVE;

        /*
         * 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 anyway in case we booted
         * with RB_ASKNAME and get selected as the boot device.
         */
        mountroothook_establish(fd_mountroot_hook, fd->sc_dev);

        rnd_attach_source(&fd->rnd_source, device_xname(fd->sc_dev),
            RND_TYPE_DISK, RND_FLAG_DEFAULT);
}

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

        if (type >= __arraycount(fd_types))
                return NULL;
        return &fd_types[type];
}

static void
fdstrategy(struct buf *bp)
{
        struct fd_softc *fd;
        int unit;
        int sz;
        int s;

        unit = FDUNIT(bp->b_dev);
        fd = device_lookup_private(&fd_cd, unit);
        if (fd == NULL) {
                bp->b_error = EINVAL;
                goto done;
        }

        if (bp->b_blkno < 0 ||
            ((bp->b_bcount % FDC_BSIZE) != 0 &&
             (bp->b_flags & B_FORMAT) == 0)) {
                DPRINTF(("fdstrategy: unit=%d, blkno=%" PRId64 ", "
                    "bcount=%d\n", unit,
                    bp->b_blkno, bp->b_bcount));
                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 << (fd->sc_type->secsize - 2))) {
                sz = (fd->sc_type->size << (fd->sc_type->secsize - 2))
                     - bp->b_blkno;
                if (sz == 0) {
                        /* If exactly at end of disk, return EOF. */
                        bp->b_resid = bp->b_bcount;
                        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 * (1 << (fd->sc_type->secsize - 2)));

        DPRINTF(("fdstrategy: %s b_blkno %" PRId64 " b_bcount %d cylin %d\n",
            bp->b_flags & B_READ ? "read" : "write",
            bp->b_blkno, bp->b_bcount, bp->b_cylinder));
        /* 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;

                fdc = device_private(device_parent(fd->sc_dev));
                if (fdc->sc_state == DEVIDLE) {
                        printf("fdstrategy: controller inactive\n");
                        fdcstart(fdc);
                }
        }
#endif
        splx(s);
        return;

 done:
        /* Toss transfer; we're done early. */
        biodone(bp);
}

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

        /* 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);
}

static 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;

        rnd_add_uint32(&fd->rnd_source, bp->b_blkno);

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

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

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

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

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

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

        DPRINTF(("fd_set_motor:\n"));
        for (n = 0; n < 4; n++) {
                fd = fdc->sc_fd[n];
                if (fd != NULL && (fd->sc_flags & FD_MOTOR) != 0)
                        bus_space_write_1(fdc->sc_iot, fdc->sc_ioh, fdctl,
                            0x80 | (fd->sc_type->rate << 4)| n);
        }
}

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

        DPRINTF(("fd_motor_off:\n"));

        s = splbio();
        fd->sc_flags &= ~(FD_MOTOR | FD_MOTOR_WAIT);
        bus_space_write_1(fdc->sc_iot, fdc->sc_ioh, fdctl,
            (fd->sc_type->rate << 4) | fd->sc_drive);
#if 0
        fd_set_motor(fdc, 0); /* XXX */
#endif
        splx(s);
}

#if 0 /* on x68k motor on triggers interrupts by state change of ready line. */
static void
fd_motor_on(void *arg)
{
        struct fd_softc *fd = arg;
        struct fdc_softc *fdc = device_private(device_parent(fd->sc_dev));
        int s;

        DPRINTF(("fd_motor_on:\n"));

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

static int
fdcresult(struct fdc_softc *fdc)
{
        bus_space_tag_t iot = fdc->sc_iot;
        bus_space_handle_t ioh = fdc->sc_ioh;
        uint8_t i;
        int j, n;

        n = 0;
        for (j = 100000; j != 0; 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, "fdcresult: overrun\n");
                                return -1;
                        }
                        fdc->sc_status[n++] =
                            bus_space_read_1(iot, ioh, fddata);
                }
                delay(10);
        }
        log(LOG_ERR, "fdcresult: timeout\n");
        return -1;
}

static 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;
}

static int
fdopen(dev_t dev, int flags, int mode, struct lwp *l)
{
        int unit;
        struct fd_softc *fd;
        struct fd_type *type;
        struct fdc_softc *fdc;

        unit = FDUNIT(dev);
        fd = device_lookup_private(&fd_cd, 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;

        fdc = device_private(device_parent(fd->sc_dev));
        if ((fd->sc_flags & FD_OPEN) == 0) {
                /* Lock eject button */
                bus_space_write_1(fdc->sc_iot, fdc->sc_ioh, fdout,
                    0x40 | (1 << unit));
                bus_space_write_1(fdc->sc_iot, fdc->sc_ioh, fdout, 0x40);
        }

        fd->sc_type = type;
        fd->sc_cylin = -1;

        switch (mode) {
        case S_IFCHR:
                fd->sc_flags |= FD_COPEN;
                break;
        case S_IFBLK:
                fd->sc_flags |= FD_BOPEN;
                break;
        }

        fdgetdisklabel(fd, dev);

        return 0;
}

static int
fdclose(dev_t dev, int flags, int mode, struct lwp *l)
{
        int unit = FDUNIT(dev);
        struct fd_softc *fd = device_lookup_private(&fd_cd, unit);
        struct fdc_softc *fdc = device_private(device_parent(fd->sc_dev));

        DPRINTF(("fdclose %d\n", unit));

        switch (mode) {
        case S_IFCHR:
                fd->sc_flags &= ~FD_COPEN;
                break;
        case S_IFBLK:
                fd->sc_flags &= ~FD_BOPEN;
                break;
        }

        /* clear flags */
        fd->sc_opts &= ~(FDOPT_NORETRY | FDOPT_SILENT);

        if ((fd->sc_flags & FD_OPEN) == 0) {
                bus_space_write_1(fdc->sc_iot, fdc->sc_ioh, fdout,
                    (1 << unit));
                bus_space_write_1(fdc->sc_iot, fdc->sc_ioh, fdout, 0);
        }
        return 0;
}

static 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)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
        }
}

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

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

        printf("%s: %s: state %d", device_xname(dv), s, fdc->sc_state);
        fdcpstatus(n, fdc);
}

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

        s = splbio();
        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);
}

#if 0
static void
fdcpseudointr(void *arg)
{
        int s;
        struct fdc_softc *fdc = arg;

        /* just ensure it has the right spl */
        s = splbio();
        (void)fdcintr(fdc);
        splx(s);
}
#endif

static 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, pos, i, sectrac, nblks;
        int tmp;
        struct fd_type *type;
        struct ne7_fd_formb *finfo = NULL;

 loop:
        fd = TAILQ_FIRST(&fdc->sc_drives);
        if (fd == NULL) {
                DPRINTF(("fdcintr: set DEVIDLE\n"));
                if (fdc->sc_state == DEVIDLE) {
                        if ((intio_get_sicilian_intr() & SICILIAN_STAT_FDC)
                            != 0) {
                                out_fdc(iot, ioh, NE7CMD_SENSEI);
                                if ((tmp = fdcresult(fdc)) != 2 ||
                                    (st0 & 0xf8) != 0x20) {
                                        goto loop;
                                }
                        }
                }
                /* no drives waiting; end */
                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;
        }

        if (bp->b_flags & B_FORMAT)
                finfo = (struct ne7_fd_formb *)bp->b_data;

        switch (fdc->sc_state) {
        case DEVIDLE:
                DPRINTF(("fdcintr: in DEVIDLE\n"));
                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 other drives. */
                        for (i = 0; i < 4; i++) {
                                struct fd_softc *ofd = fdc->sc_fd[i];
                                if (ofd != NULL &&
                                    (ofd->sc_flags & FD_MOTOR) != 0) {
                                        callout_stop(&ofd->sc_motoroff_ch);
                                        ofd->sc_flags &=
                                            ~(FD_MOTOR | FD_MOTOR_WAIT);
                                        break;
                                }
                        }
                        fd->sc_flags |= FD_MOTOR | FD_MOTOR_WAIT;
                        fd_set_motor(fdc, 0);
                        fdc->sc_state = MOTORWAIT;
#if 0   /* no need to callout on x68k; motor on will trigger interrupts */
                        /* allow .5s for motor to stabilize */
                        callout_reset(&fd->sc_motoron_ch, hz / 2,
                            fd_motor_on, fd);
#endif
                        return 1;
                }
                /* Make sure the right drive is selected. */
                fd_set_motor(fdc, 0);

                /* fall through */
        case DOSEEK:
        doseek:
                DPRINTF(("fdcintr: in DOSEEK\n"));
                if (fd->sc_cylin == bp->b_cylinder)
                        goto doio;

                out_fdc(iot, ioh, NE7CMD_SPECIFY);      /* specify command */
                out_fdc(iot, ioh, 0xd0);                /* XXX const */
                out_fdc(iot, ioh, 0x10);

                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:
                DPRINTF(("fdcintr: DOIO: "));
                type = fd->sc_type;
                if (finfo != NULL)
                        fd->sc_skip = (char *)&(finfo->fd_formb_cylno(0)) -
                            (char *)finfo;
                sectrac = type->sectrac;
                pos = fd->sc_blkno % (sectrac * (1 << (type->secsize - 2)));
                sec = pos / (1 << (type->secsize - 2));
                if (finfo != NULL || type->secsize == 2) {
                        fd->sc_part = SEC_P11;
                        nblks = (sectrac - sec) << (type->secsize - 2);
                        nblks = uimin(nblks, fd->sc_bcount / FDC_BSIZE);
                        DPRINTF(("nblks(0)"));
                } else if ((fd->sc_blkno % 2) == 0) {
                        if (fd->sc_bcount & 0x00000200) {
                                if (fd->sc_bcount == FDC_BSIZE) {
                                        fd->sc_part = SEC_P10;
                                        nblks = 1;
                                        DPRINTF(("nblks(1)"));
                                } else {
                                        fd->sc_part = SEC_P11;
                                        nblks = (sectrac - sec) * 2;
                                        nblks = uimin(nblks,
                                            fd->sc_bcount / FDC_BSIZE - 1);
                                        DPRINTF(("nblks(2)"));
                                }
                        } else {
                                fd->sc_part = SEC_P11;
                                nblks = (sectrac - sec) << (type->secsize - 2);
                                nblks = uimin(nblks, fd->sc_bcount / FDC_BSIZE);
                                DPRINTF(("nblks(3)"));
                        }
                } else {
                        fd->sc_part = SEC_P01;
                        nblks = 1;
                        DPRINTF(("nblks(4)"));
                }
                nblks = uimin(nblks, FDC_MAXIOSIZE / FDC_BSIZE);
                DPRINTF((" %d\n", nblks));
                fd->sc_nblks = nblks;
                fd->sc_nbytes =
                    (finfo != NULL) ? bp->b_bcount : nblks * FDC_BSIZE;
                head = (fd->sc_blkno
                    % (type->seccyl * (1 << (type->secsize - 2))))
                    / (type->sectrac * (1 << (type->secsize - 2)));

#ifdef DIAGNOSTIC
                {
                        int block;
                        block = ((fd->sc_cylin * type->heads + head) *
                            type->sectrac + sec) * (1 << (type->secsize - 2));
                        block += (fd->sc_part == SEC_P01) ? 1 : 0;
                        if (block != fd->sc_blkno) {
                                printf("C H R N: %d %d %d %d\n",
                                    fd->sc_cylin, head, sec, type->secsize);
                                printf("fdcintr: doio: block %d != blkno %"
                                    PRId64 "\n",
                                    block, fd->sc_blkno);
#ifdef DDB
                                Debugger();
#endif
                        }
                }
#endif
                read = bp->b_flags & B_READ;
                DPRINTF(("fdcintr: %s drive %d track %d "
                    "head %d sec %d nblks %d, skip %d\n",
                    read ? "read" : "write", fd->sc_drive, fd->sc_cylin,
                    head, sec, nblks, fd->sc_skip));
                DPRINTF(("C H R N: %d %d %d %d\n", fd->sc_cylin, head, sec,
                    type->secsize));

                if (finfo == NULL && fd->sc_part != SEC_P11)
                        goto docopy;

                fdc_dmastart(fdc, read, (char *)bp->b_data + fd->sc_skip,
                    fd->sc_nbytes);
                if (finfo != NULL) {
                        /* formatting */
                        if (out_fdc(iot, ioh, NE7CMD_FORMAT) < 0) {
                                fdc->sc_errors = 4;
                                fdcretry(fdc);
                                goto loop;
                        }
                        out_fdc(iot, ioh, (head << 2) | fd->sc_drive);
                        out_fdc(iot, ioh, finfo->fd_formb_secshift);
                        out_fdc(iot, ioh, finfo->fd_formb_nsecs);
                        out_fdc(iot, ioh, finfo->fd_formb_gaplen);
                        out_fdc(iot, ioh, finfo->fd_formb_fillbyte);
                } else {
                        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, bp->b_cylinder);      /* cylinder */
                        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 DOCOPY:
        docopy:
                DPRINTF(("fdcintr: DOCOPY:\n"));
                type = fd->sc_type;
                head = (fd->sc_blkno
                    % (type->seccyl * (1 << (type->secsize - 2))))
                    / (type->sectrac * (1 << (type->secsize - 2)));
                pos = fd->sc_blkno %
                    (type->sectrac * (1 << (type->secsize - 2)));
                sec = pos / (1 << (type->secsize - 2));
                fdc_dmastart(fdc, B_READ, fd->sc_copybuf, 1024);
                out_fdc(iot, ioh, NE7CMD_READ);         /* READ */
                out_fdc(iot, ioh, (head << 2) | fd->sc_drive);
                out_fdc(iot, ioh, bp->b_cylinder);      /* cylinder */
                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 = COPYCOMPLETE;
                /* allow 2 seconds for operation */
                callout_reset(&fdc->sc_timo_ch, 2 * hz, fdctimeout, fdc);
                return 1;                               /* will return later */

        case DOIOHALF:
        doiohalf:
                DPRINTF((" DOIOHALF:\n"));

                type = fd->sc_type;
                sectrac = type->sectrac;
                pos = fd->sc_blkno % (sectrac * (1 << (type->secsize - 2)));
                sec = pos / (1 << (type->secsize - 2));
                head = (fd->sc_blkno
                    % (type->seccyl * (1 << (type->secsize - 2))))
                    / (type->sectrac * (1 << (type->secsize - 2)));
#ifdef DIAGNOSTIC
                {
                        int block;
                        block = ((fd->sc_cylin * type->heads + head) *
                            type->sectrac + sec) * (1 << (type->secsize - 2));
                        block += (fd->sc_part == SEC_P01) ? 1 : 0;
                        if (block != fd->sc_blkno) {
                                printf("fdcintr: block %d != blkno %" PRId64
                                    "\n",
                                    block, fd->sc_blkno);
#ifdef DDB
                                Debugger();
#endif
                        }
                }
#endif
                if ((read = bp->b_flags & B_READ)) {
                        memcpy((char *)bp->b_data + fd->sc_skip, fd->sc_copybuf
                            + (fd->sc_part & SEC_P01 ? FDC_BSIZE : 0),
                            FDC_BSIZE);
                        fdc->sc_state = IOCOMPLETE;
                        goto iocomplete2;
                } else {
                        memcpy((char *)fd->sc_copybuf
                            + (fd->sc_part & SEC_P01 ? FDC_BSIZE : 0),
                            (char *)bp->b_data + fd->sc_skip, FDC_BSIZE);
                        fdc_dmastart(fdc, read, fd->sc_copybuf, 1024);
                }
                out_fdc(iot, ioh, NE7CMD_WRITE);        /* WRITE */
                out_fdc(iot, ioh, (head << 2) | fd->sc_drive);
                out_fdc(iot, ioh, bp->b_cylinder);      /* cylinder */
                out_fdc(iot, ioh, head);
                out_fdc(iot, ioh, sec + 1);             /* sector +1 */
                out_fdc(iot, ioh, fd->sc_type->secsize); /* sector size */
                out_fdc(iot, ioh, sectrac);             /* sectors/track */
                out_fdc(iot, ioh, fd->sc_type->gap1);   /* gap1 size */
                out_fdc(iot, ioh, fd->sc_type->datalen); /* data length */
                fdc->sc_state = IOCOMPLETE;
                /* 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 */
#if 0
                callout_reset(&fdc->sc_intr_ch, hz / 50, fdcpseudointr, fdc);
#endif
                return 1;

        case SEEKCOMPLETE:
                /* Make sure seek really happened */
                DPRINTF(("fdcintr: SEEKCOMPLETE: FDC status = %x\n",
                    bus_space_read_1(fdc->sc_iot, fdc->sc_ioh, fdsts)));
                out_fdc(iot, ioh, NE7CMD_SENSEI);
                tmp = fdcresult(fdc);
                if ((st0 & 0xf8) == 0xc0) {
                        DPRINTF(("fdcintr: first seek!\n"));
                        fdc->sc_state = DORECAL;
                        goto loop;
                } else if (tmp != 2 ||
                    (st0 & 0xf8) != 0x20 ||
                    cyl != bp->b_cylinder) {
#ifdef FDDEBUG
                        fdcstatus(fd->sc_dev, 2, "seek failed");
#endif
                        fdcretry(fdc);
                        goto loop;
                }
                fd->sc_cylin = bp->b_cylinder;
                goto doio;

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

        case IOCOMPLETE: /* IO DONE, post-analyze */
                callout_stop(&fdc->sc_timo_ch);
                DPRINTF(("fdcintr: in IOCOMPLETE\n"));
                if ((tmp = fdcresult(fdc)) != 7 || (st0 & 0xf8) != 0) {
                        fdc_dmaabort(fdc);
                        fdcstatus(fd->sc_dev, tmp, bp->b_flags & B_READ ?
                            "read failed" : "write failed");
                        printf("blkno %" PRId64 " nblks %d\n",
                            fd->sc_blkno, fd->sc_nblks);
                        fdcretry(fdc);
                        goto loop;
                }
        iocomplete2:
                if (fdc->sc_errors) {
                        diskerr(bp, "fd", "soft error (corrected)", LOG_PRINTF,
                            fd->sc_skip / FDC_BSIZE, (struct disklabel *)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;
                DPRINTF(("fd->sc_bcount = %d\n", fd->sc_bcount));
                if (finfo == NULL && fd->sc_bcount > 0) {
                        bp->b_cylinder = fd->sc_blkno
                            / (fd->sc_type->seccyl
                            * (1 << (fd->sc_type->secsize - 2)));
                        goto doseek;
                }
                fdfinish(fd, bp);
                goto loop;

        case COPYCOMPLETE: /* IO DONE, post-analyze */
                DPRINTF(("fdcintr: COPYCOMPLETE:"));
                callout_stop(&fdc->sc_timo_ch);
                if ((tmp = fdcresult(fdc)) != 7 || (st0 & 0xf8) != 0) {
                        printf("fdcintr: resnum=%d, st0=%x\n", tmp, st0);
                        fdc_dmaabort(fdc);
                        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);
                        fdcretry(fdc);
                        goto loop;
                }
                goto doiohalf;

        case DORESET:
                DPRINTF(("fdcintr: in DORESET\n"));
                /* 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:
                DPRINTF(("fdcintr: in RESETCOMPLETE\n"));
                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:
                DPRINTF(("fdcintr: in DORECAL\n"));
                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:
                DPRINTF(("fdcintr: in RECALWAIT\n"));
                callout_stop(&fdc->sc_timo_ch);
                fdc->sc_state = RECALCOMPLETE;
                /* allow 1/30 second for heads to settle */
#if 0
                callout_reset(&fdc->sc_intr_ch, hz / 30, fdcpseudointr, fdc);
#endif
                return 1;                       /* will return later */

        case RECALCOMPLETE:
                DPRINTF(("fdcintr: in RECALCOMPLETE\n"));
                out_fdc(iot, ioh, NE7CMD_SENSEI);
                tmp = fdcresult(fdc);
                if ((st0 & 0xf8) == 0xc0) {
                        DPRINTF(("fdcintr: first seek!\n"));
                        fdc->sc_state = DORECAL;
                        goto loop;
                } else if (tmp != 2 || (st0 & 0xf8) != 0x20 || cyl != 0) {
#ifdef FDDEBUG
                        fdcstatus(fd->sc_dev, 2, "recalibrate failed");
#endif
                        fdcretry(fdc);
                        goto loop;
                }
                fd->sc_cylin = 0;
                goto doseek;

        case MOTORWAIT:
#if 0 /* on x68k motor on triggers interrupts by state change of ready line. */
                if (fd->sc_flags & FD_MOTOR_WAIT)
                        return 1;               /* time's not up yet */
#else
                /* check drive ready by state change interrupt */
                KASSERT(fd->sc_flags & FD_MOTOR_WAIT);
                out_fdc(iot, ioh, NE7CMD_SENSEI);
                tmp = fdcresult(fdc);
                if (tmp != 2 || (st0 & 0xc0) != 0xc0 /* ready changed */) {
                        printf("%s: unexpected interrupt during MOTORWAIT",
                            device_xname(fd->sc_dev));
                        fdcpstatus(7, fdc);
                        return 1;
                }
                fd->sc_flags &= ~FD_MOTOR_WAIT;
#endif
                goto doseek;

        default:
                fdcstatus(fd->sc_dev, 0, "stray interrupt");
                return 1;
        }
#ifdef DIAGNOSTIC
        panic("fdcintr: impossible");
#endif
#undef  st0
#undef  cyl
}

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

        DPRINTF(("fdcretry:\n"));
        fd = TAILQ_FIRST(&fdc->sc_drives);
        bp = bufq_peek(fd->sc_q);

        if (fd->sc_opts & FDOPT_NORETRY)
                goto fail;

        switch (fdc->sc_errors) {
        case 0:
                /* try again */
                fdc->sc_state = SEEKCOMPLETE;
                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:
        fail:
                if ((fd->sc_opts & FDOPT_SILENT) == 0) {
                        diskerr(bp, "fd", "hard error", LOG_PRINTF,
                            fd->sc_skip, (struct disklabel *)NULL);
                        fdcpstatus(7, fdc);
                }

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

static 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 fdc_softc *fdc = device_private(device_parent(fd->sc_dev));
        struct fdformat_parms *form_parms;
        struct fdformat_cmd *form_cmd;
        struct ne7_fd_formb *fd_formb;
        int part = DISKPART(dev);
        struct disklabel buffer;
        int error;
        unsigned int scratch;
        int il[FD_MAX_NSEC + 1];
        int i, j;

        error = disk_ioctl(&fd->sc_dk, dev, cmd, addr, flag, l);
        if (error != EPASSTHROUGH)
                return error;

        DPRINTF(("fdioctl:"));
        switch (cmd) {
        case DIOCWLABEL:
                DPRINTF(("DIOCWLABEL\n"));
                if ((flag & FWRITE) == 0)
                        return EBADF;
                /* XXX do something */
                return 0;

        case DIOCWDINFO:
                DPRINTF(("DIOCWDINFO\n"));
                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;

        case FDIOCGETFORMAT:
                DPRINTF(("FDIOCGETFORMAT\n"));
                form_parms = (struct fdformat_parms *)addr;
                form_parms->fdformat_version = FDFORMAT_VERSION;
                form_parms->nbps = 128 * (1 << fd->sc_type->secsize);
                form_parms->ncyl = fd->sc_type->cyls;
                form_parms->nspt = fd->sc_type->sectrac;
                form_parms->ntrk = fd->sc_type->heads;
                form_parms->stepspercyl = fd->sc_type->step;
                form_parms->gaplen = fd->sc_type->gap2;
                form_parms->fillbyte = fd->sc_type->fillbyte;
                form_parms->interleave = fd->sc_type->interleave;
                switch (fd->sc_type->rate) {
                case FDC_500KBPS:
                        form_parms->xfer_rate = 500 * 1024;
                        break;
                case FDC_300KBPS:
                        form_parms->xfer_rate = 300 * 1024;
                        break;
                case FDC_250KBPS:
                        form_parms->xfer_rate = 250 * 1024;
                        break;
                default:
                        return EINVAL;
                }
                return 0;

        case FDIOCSETFORMAT:
                DPRINTF(("FDIOCSETFORMAT\n"));
                if((flag & FWRITE) == 0)
                        return EBADF;   /* must be opened for writing */
                form_parms = (struct fdformat_parms *)addr;
                if (form_parms->fdformat_version != FDFORMAT_VERSION)
                        return EINVAL;  /* wrong version of formatting prog */

                scratch = form_parms->nbps >> 7;
                if ((form_parms->nbps & 0x7f) || ffs(scratch) == 0 ||
                    scratch & ~(1 << (ffs(scratch) - 1)))
                        /* not a power-of-two multiple of 128 */
                        return EINVAL;

                switch (form_parms->xfer_rate) {
                case 500 * 1024:
                        fd->sc_type->rate = FDC_500KBPS;
                        break;
                case 300 * 1024:
                        fd->sc_type->rate = FDC_300KBPS;
                        break;
                case 250 * 1024:
                        fd->sc_type->rate = FDC_250KBPS;
                        break;
                default:
                        return EINVAL;
                }

                if (form_parms->nspt > FD_MAX_NSEC ||
                    form_parms->fillbyte > 0xff ||
                    form_parms->interleave > 0xff)
                        return EINVAL;
                fd->sc_type->sectrac = form_parms->nspt;
                if (form_parms->ntrk != 2 && form_parms->ntrk != 1)
                        return EINVAL;
                fd->sc_type->heads = form_parms->ntrk;
                fd->sc_type->seccyl = form_parms->nspt * form_parms->ntrk;
                fd->sc_type->secsize = ffs(scratch)-1;
                fd->sc_type->gap2 = form_parms->gaplen;
                fd->sc_type->cyls = form_parms->ncyl;
                fd->sc_type->size = fd->sc_type->seccyl * form_parms->ncyl *
                    form_parms->nbps / DEV_BSIZE;
                fd->sc_type->step = form_parms->stepspercyl;
                fd->sc_type->fillbyte = form_parms->fillbyte;
                fd->sc_type->interleave = form_parms->interleave;
                return 0;

        case FDIOCFORMAT_TRACK:
                DPRINTF(("FDIOCFORMAT_TRACK\n"));
                if ((flag & FWRITE) == 0)
                        return EBADF;   /* must be opened for writing */
                form_cmd = (struct fdformat_cmd *)addr;
                if (form_cmd->formatcmd_version != FDFORMAT_VERSION)
                        return EINVAL;  /* wrong version of formatting prog */

                if (form_cmd->head >= fd->sc_type->heads ||
                    form_cmd->cylinder >= fd->sc_type->cyls) {
                        return EINVAL;
                }

                fd_formb = malloc(sizeof(struct ne7_fd_formb),
                    M_TEMP, M_WAITOK);
                fd_formb->head = form_cmd->head;
                fd_formb->cyl = form_cmd->cylinder;
                fd_formb->transfer_rate = fd->sc_type->rate;
                fd_formb->fd_formb_secshift = fd->sc_type->secsize;
                fd_formb->fd_formb_nsecs = fd->sc_type->sectrac;
                fd_formb->fd_formb_gaplen = fd->sc_type->gap2;
                fd_formb->fd_formb_fillbyte = fd->sc_type->fillbyte;

                memset(il, 0, sizeof il);
                for (j = 0, i = 1; i <= fd_formb->fd_formb_nsecs; i++) {
                        while (il[(j % fd_formb->fd_formb_nsecs) + 1])
                                j++;
                        il[(j % fd_formb->fd_formb_nsecs)+  1] = i;
                        j += fd->sc_type->interleave;
                }
                for (i = 0; i < fd_formb->fd_formb_nsecs; i++) {
                        fd_formb->fd_formb_cylno(i) = form_cmd->cylinder;
                        fd_formb->fd_formb_headno(i) = form_cmd->head;
                        fd_formb->fd_formb_secno(i) = il[i + 1];
                        fd_formb->fd_formb_secsize(i) = fd->sc_type->secsize;
                }

                error = fdformat(dev, fd_formb, l);
                free(fd_formb, M_TEMP);
                return error;

        case FDIOCGETOPTS:              /* get drive options */
                DPRINTF(("FDIOCGETOPTS\n"));
                *(int *)addr = fd->sc_opts;
                return 0;

        case FDIOCSETOPTS:              /* set drive options */
                DPRINTF(("FDIOCSETOPTS\n"));
                fd->sc_opts = *(int *)addr;
                return 0;

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

        case DIOCEJECT:
                DPRINTF(("DIOCEJECT\n"));
                if (*(int *)addr == 0) {
                        /*
                         * Don't force eject: check that we are the only
                         * partition open. If so, unlock it.
                         */
                        if ((fd->sc_dk.dk_openmask & ~(1 << part)) != 0 ||
                            fd->sc_dk.dk_bopenmask + fd->sc_dk.dk_copenmask !=
                            fd->sc_dk.dk_openmask) {
                                return EBUSY;
                        }
                }
                /* FALLTHROUGH */
        case ODIOCEJECT:
                DPRINTF(("ODIOCEJECT\n"));
                fd_do_eject(fdc, FDUNIT(dev));
                return 0;

        default:
                return ENOTTY;
        }

#ifdef DIAGNOSTIC
        panic("fdioctl: impossible");
#endif
}

static int
fdformat(dev_t dev, struct ne7_fd_formb *finfo, struct lwp *l)
{
        int rv = 0;
        struct fd_softc *fd = device_lookup_private(&fd_cd, FDUNIT(dev));
        struct fd_type *type = fd->sc_type;
        struct buf *bp;

        /* set up a buffer header for fdstrategy() */
        bp = getiobuf(NULL, false);
        if (bp == NULL)
                return ENOBUFS;

        bp->b_cflags = BC_BUSY;
        bp->b_flags = B_PHYS | B_FORMAT;
        bp->b_proc = l->l_proc;
        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) * (128 << type->secsize) / DEV_BSIZE;

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

#ifdef FDDEBUG
        printf("fdformat: blkno %" PRIx64 " count %x\n",
            bp->b_blkno, bp->b_bcount);
#endif

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

        /* ...and wait for it to complete */
        rv = biowait(bp);
        putiobuf(bp);
        return rv;
}

static void
fd_do_eject(struct fdc_softc *fdc, int unit)
{

        bus_space_write_1(fdc->sc_iot, fdc->sc_ioh, fdout, 0x20 | (1 << unit));
        DELAY(1); /* XXX */
        bus_space_write_1(fdc->sc_iot, fdc->sc_ioh, fdout, 0x20);
}

/*
 * Build disk label. For now we only create a label from what we know
 * from 'sc'.
 */
static int
fdgetdisklabel(struct fd_softc *sc, dev_t dev)
{
        struct disklabel *lp;
        int part;

        DPRINTF(("fdgetdisklabel()\n"));

        part = DISKPART(dev);
        lp = sc->sc_dk.dk_label;
        memset(lp, 0, sizeof(struct disklabel));

        lp->d_secsize     = 128 << sc->sc_type->secsize;
        lp->d_ntracks     = sc->sc_type->heads;
        lp->d_nsectors    = sc->sc_type->sectrac;
        lp->d_secpercyl   = lp->d_ntracks * lp->d_nsectors;
        lp->d_ncylinders  = sc->sc_type->size / lp->d_secpercyl;
        lp->d_secperunit  = sc->sc_type->size;

        lp->d_type        = DKTYPE_FLOPPY;
        lp->d_rpm         = 300;        /* XXX */
        lp->d_interleave  = 1;          /* FIXME: is this OK?           */
        lp->d_bbsize      = 0;
        lp->d_sbsize      = 0;
        lp->d_npartitions = part + 1;
#define STEP_DELAY      6000    /* 6ms (6000us) delay after stepping    */
        lp->d_trkseek     = STEP_DELAY; /* XXX */
        lp->d_magic       = DISKMAGIC;
        lp->d_magic2      = DISKMAGIC;
        lp->d_checksum    = dkcksum(lp);
        lp->d_partitions[part].p_size   = lp->d_secperunit;
        lp->d_partitions[part].p_fstype = FS_UNUSED;
        lp->d_partitions[part].p_fsize  = 1024;
        lp->d_partitions[part].p_frag   = 8;

        return 0;
}

/*
 * Mountroot hook: prompt the user to enter the root file system
 * floppy.
 */
static void
fd_mountroot_hook(device_t dev)
{
        struct fd_softc *fd = device_private(dev);
        struct fdc_softc *fdc = device_private(device_parent(fd->sc_dev));
        int c;

        /* XXX device_unit() abuse */
        fd_do_eject(fdc, device_unit(dev));
        printf("Insert filesystem floppy and press return.");
        for (;;) {
                c = cngetc();
                if ((c == '\r') || (c == '\n')) {
                        printf("\n");
                        break;
                }
        }
}