gwj / at91sam9263 · Files

/*

 * QEMU Floppy disk emulator (Intel 82078)

 *

 * Copyright (c) 2003, 2007 Jocelyn Mayer

 * Copyright (c) 2008 Hervé Poussineau

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

/*
 * The controller is used in Sun4m systems in a slightly different
 * way. There are changes in DOR register and DMA is not available.
 */

#include "hw.h"
#include "fdc.h"
#include "block.h"
#include "qemu-timer.h"
#include "isa.h"

#include "sysbus.h"

#include "qdev-addr.h"

/********************************************************/
/* debug Floppy devices */
//#define DEBUG_FLOPPY

#ifdef DEBUG_FLOPPY

#define FLOPPY_DPRINTF(fmt, ...)                                \
    do { printf("FLOPPY: " fmt , ## __VA_ARGS__); } while (0)

#else

#define FLOPPY_DPRINTF(fmt, ...)

#endif

#define FLOPPY_ERROR(fmt, ...)                                          \
    do { printf("FLOPPY ERROR: %s: " fmt, __func__ , ## __VA_ARGS__); } while (0)

/********************************************************/
/* Floppy drive emulation                               */

#define GET_CUR_DRV(fdctrl) ((fdctrl)->cur_drv)
#define SET_CUR_DRV(fdctrl, drive) ((fdctrl)->cur_drv = (drive))

/* Will always be a fixed parameter for us */

#define FD_SECTOR_LEN          512
#define FD_SECTOR_SC           2   /* Sector size code */
#define FD_RESET_SENSEI_COUNT  4   /* Number of sense interrupts on RESET */

/* Floppy disk drive emulation */
typedef enum fdisk_type_t {
    FDRIVE_DISK_288   = 0x01, /* 2.88 MB disk           */
    FDRIVE_DISK_144   = 0x02, /* 1.44 MB disk           */
    FDRIVE_DISK_720   = 0x03, /* 720 kB disk            */

    FDRIVE_DISK_USER  = 0x04, /* User defined geometry  */
    FDRIVE_DISK_NONE  = 0x05, /* No disk                */

} fdisk_type_t;

typedef enum fdrive_type_t {
    FDRIVE_DRV_144  = 0x00,   /* 1.44 MB 3"5 drive      */
    FDRIVE_DRV_288  = 0x01,   /* 2.88 MB 3"5 drive      */
    FDRIVE_DRV_120  = 0x02,   /* 1.2  MB 5"25 drive     */
    FDRIVE_DRV_NONE = 0x03,   /* No drive connected     */
} fdrive_type_t;

typedef enum fdisk_flags_t {
    FDISK_DBL_SIDES  = 0x01,
} fdisk_flags_t;

typedef struct fdrive_t {
    BlockDriverState *bs;
    /* Drive status */
    fdrive_type_t drive;
    uint8_t perpendicular;    /* 2.88 MB access mode    */
    /* Position */
    uint8_t head;
    uint8_t track;
    uint8_t sect;
    /* Media */

    fdisk_flags_t flags;

    uint8_t last_sect;        /* Nb sector per track    */
    uint8_t max_track;        /* Nb of tracks           */

    uint16_t bps;             /* Bytes per sector       */

    uint8_t ro;               /* Is read-only           */
} fdrive_t;

static void fd_init (fdrive_t *drv, BlockDriverState *bs)

{
    /* Drive */

    drv->bs = bs;

    drv->drive = FDRIVE_DRV_NONE;

    drv->perpendicular = 0;
    /* Disk */

    drv->last_sect = 0;

    drv->max_track = 0;
}

static int _fd_sector (uint8_t head, uint8_t track,

                       uint8_t sect, uint8_t last_sect)

{
    return (((track * 2) + head) * last_sect) + sect - 1;
}

/* Returns current position, in sectors, for given drive */
static int fd_sector (fdrive_t *drv)
{
    return _fd_sector(drv->head, drv->track, drv->sect, drv->last_sect);
}

/* Seek to a new position:
 * returns 0 if already on right track
 * returns 1 if track changed
 * returns 2 if track is invalid
 * returns 3 if sector is invalid
 * returns 4 if seek is disabled
 */

static int fd_seek (fdrive_t *drv, uint8_t head, uint8_t track, uint8_t sect,
                    int enable_seek)
{
    uint32_t sector;

    int ret;

    if (track > drv->max_track ||

        (head != 0 && (drv->flags & FDISK_DBL_SIDES) == 0)) {

        FLOPPY_DPRINTF("try to read %d %02x %02x (max=%d %d %02x %02x)\n",
                       head, track, sect, 1,
                       (drv->flags & FDISK_DBL_SIDES) == 0 ? 0 : 1,
                       drv->max_track, drv->last_sect);

        return 2;
    }
    if (sect > drv->last_sect) {

        FLOPPY_DPRINTF("try to read %d %02x %02x (max=%d %d %02x %02x)\n",
                       head, track, sect, 1,
                       (drv->flags & FDISK_DBL_SIDES) == 0 ? 0 : 1,
                       drv->max_track, drv->last_sect);

        return 3;
    }
    sector = _fd_sector(head, track, sect, drv->last_sect);

    ret = 0;

    if (sector != fd_sector(drv)) {
#if 0
        if (!enable_seek) {
            FLOPPY_ERROR("no implicit seek %d %02x %02x (max=%d %02x %02x)\n",
                         head, track, sect, 1, drv->max_track, drv->last_sect);
            return 4;
        }
#endif
        drv->head = head;

        if (drv->track != track)
            ret = 1;

        drv->track = track;
        drv->sect = sect;
    }

    return ret;

}

/* Set drive back to track 0 */
static void fd_recalibrate (fdrive_t *drv)
{
    FLOPPY_DPRINTF("recalibrate\n");
    drv->head = 0;
    drv->track = 0;
    drv->sect = 1;
}

/* Recognize floppy formats */
typedef struct fd_format_t {
    fdrive_type_t drive;
    fdisk_type_t  disk;
    uint8_t last_sect;
    uint8_t max_track;
    uint8_t max_head;

    const char *str;

} fd_format_t;

static const fd_format_t fd_formats[] = {

    /* First entry is default format */
    /* 1.44 MB 3"1/2 floppy disks */
    { FDRIVE_DRV_144, FDRIVE_DISK_144, 18, 80, 1, "1.44 MB 3\"1/2", },
    { FDRIVE_DRV_144, FDRIVE_DISK_144, 20, 80, 1,  "1.6 MB 3\"1/2", },
    { FDRIVE_DRV_144, FDRIVE_DISK_144, 21, 80, 1, "1.68 MB 3\"1/2", },
    { FDRIVE_DRV_144, FDRIVE_DISK_144, 21, 82, 1, "1.72 MB 3\"1/2", },
    { FDRIVE_DRV_144, FDRIVE_DISK_144, 21, 83, 1, "1.74 MB 3\"1/2", },
    { FDRIVE_DRV_144, FDRIVE_DISK_144, 22, 80, 1, "1.76 MB 3\"1/2", },
    { FDRIVE_DRV_144, FDRIVE_DISK_144, 23, 80, 1, "1.84 MB 3\"1/2", },
    { FDRIVE_DRV_144, FDRIVE_DISK_144, 24, 80, 1, "1.92 MB 3\"1/2", },
    /* 2.88 MB 3"1/2 floppy disks */
    { FDRIVE_DRV_288, FDRIVE_DISK_288, 36, 80, 1, "2.88 MB 3\"1/2", },
    { FDRIVE_DRV_288, FDRIVE_DISK_288, 39, 80, 1, "3.12 MB 3\"1/2", },
    { FDRIVE_DRV_288, FDRIVE_DISK_288, 40, 80, 1,  "3.2 MB 3\"1/2", },
    { FDRIVE_DRV_288, FDRIVE_DISK_288, 44, 80, 1, "3.52 MB 3\"1/2", },
    { FDRIVE_DRV_288, FDRIVE_DISK_288, 48, 80, 1, "3.84 MB 3\"1/2", },
    /* 720 kB 3"1/2 floppy disks */
    { FDRIVE_DRV_144, FDRIVE_DISK_720,  9, 80, 1,  "720 kB 3\"1/2", },
    { FDRIVE_DRV_144, FDRIVE_DISK_720, 10, 80, 1,  "800 kB 3\"1/2", },
    { FDRIVE_DRV_144, FDRIVE_DISK_720, 10, 82, 1,  "820 kB 3\"1/2", },
    { FDRIVE_DRV_144, FDRIVE_DISK_720, 10, 83, 1,  "830 kB 3\"1/2", },
    { FDRIVE_DRV_144, FDRIVE_DISK_720, 13, 80, 1, "1.04 MB 3\"1/2", },
    { FDRIVE_DRV_144, FDRIVE_DISK_720, 14, 80, 1, "1.12 MB 3\"1/2", },
    /* 1.2 MB 5"1/4 floppy disks */
    { FDRIVE_DRV_120, FDRIVE_DISK_288, 15, 80, 1,  "1.2 kB 5\"1/4", },
    { FDRIVE_DRV_120, FDRIVE_DISK_288, 18, 80, 1, "1.44 MB 5\"1/4", },
    { FDRIVE_DRV_120, FDRIVE_DISK_288, 18, 82, 1, "1.48 MB 5\"1/4", },
    { FDRIVE_DRV_120, FDRIVE_DISK_288, 18, 83, 1, "1.49 MB 5\"1/4", },
    { FDRIVE_DRV_120, FDRIVE_DISK_288, 20, 80, 1,  "1.6 MB 5\"1/4", },
    /* 720 kB 5"1/4 floppy disks */
    { FDRIVE_DRV_120, FDRIVE_DISK_288,  9, 80, 1,  "720 kB 5\"1/4", },
    { FDRIVE_DRV_120, FDRIVE_DISK_288, 11, 80, 1,  "880 kB 5\"1/4", },
    /* 360 kB 5"1/4 floppy disks */
    { FDRIVE_DRV_120, FDRIVE_DISK_288,  9, 40, 1,  "360 kB 5\"1/4", },
    { FDRIVE_DRV_120, FDRIVE_DISK_288,  9, 40, 0,  "180 kB 5\"1/4", },
    { FDRIVE_DRV_120, FDRIVE_DISK_288, 10, 41, 1,  "410 kB 5\"1/4", },
    { FDRIVE_DRV_120, FDRIVE_DISK_288, 10, 42, 1,  "420 kB 5\"1/4", },

    /* 320 kB 5"1/4 floppy disks */

    { FDRIVE_DRV_120, FDRIVE_DISK_288,  8, 40, 1,  "320 kB 5\"1/4", },
    { FDRIVE_DRV_120, FDRIVE_DISK_288,  8, 40, 0,  "160 kB 5\"1/4", },
    /* 360 kB must match 5"1/4 better than 3"1/2... */
    { FDRIVE_DRV_144, FDRIVE_DISK_720,  9, 80, 0,  "360 kB 3\"1/2", },
    /* end */
    { FDRIVE_DRV_NONE, FDRIVE_DISK_NONE, -1, -1, 0, NULL, },
};

/* Revalidate a disk drive after a disk change */

static void fd_revalidate (fdrive_t *drv)

{

    const fd_format_t *parse;

    uint64_t nb_sectors, size;

    int i, first_match, match;

    int nb_heads, max_track, last_sect, ro;

    FLOPPY_DPRINTF("revalidate\n");

    if (drv->bs != NULL && bdrv_is_inserted(drv->bs)) {

        ro = bdrv_is_read_only(drv->bs);
        bdrv_get_geometry_hint(drv->bs, &nb_heads, &max_track, &last_sect);
        if (nb_heads != 0 && max_track != 0 && last_sect != 0) {
            FLOPPY_DPRINTF("User defined disk (%d %d %d)",

                           nb_heads - 1, max_track, last_sect);

        } else {
            bdrv_get_geometry(drv->bs, &nb_sectors);
            match = -1;
            first_match = -1;
            for (i = 0;; i++) {
                parse = &fd_formats[i];
                if (parse->drive == FDRIVE_DRV_NONE)
                    break;
                if (drv->drive == parse->drive ||
                    drv->drive == FDRIVE_DRV_NONE) {
                    size = (parse->max_head + 1) * parse->max_track *
                        parse->last_sect;
                    if (nb_sectors == size) {
                        match = i;
                        break;
                    }
                    if (first_match == -1)
                        first_match = i;
                }
            }
            if (match == -1) {
                if (first_match == -1)
                    match = 1;
                else
                    match = first_match;
                parse = &fd_formats[match];
            }
            nb_heads = parse->max_head + 1;
            max_track = parse->max_track;
            last_sect = parse->last_sect;
            drv->drive = parse->drive;
            FLOPPY_DPRINTF("%s floppy disk (%d h %d t %d s) %s\n", parse->str,

                           nb_heads, max_track, last_sect, ro ? "ro" : "rw");

        }
        if (nb_heads == 1) {
            drv->flags &= ~FDISK_DBL_SIDES;
        } else {
            drv->flags |= FDISK_DBL_SIDES;
        }
        drv->max_track = max_track;
        drv->last_sect = last_sect;
        drv->ro = ro;

    } else {

        FLOPPY_DPRINTF("No disk in drive\n");

        drv->last_sect = 0;

        drv->max_track = 0;
        drv->flags &= ~FDISK_DBL_SIDES;

    }

}

/********************************************************/

/* Intel 82078 floppy disk controller emulation          */

static void fdctrl_reset (fdctrl_t *fdctrl, int do_irq);
static void fdctrl_reset_fifo (fdctrl_t *fdctrl);

static int fdctrl_transfer_handler (void *opaque, int nchan,
                                    int dma_pos, int dma_len);

static void fdctrl_raise_irq (fdctrl_t *fdctrl, uint8_t status0);

static uint32_t fdctrl_read_statusA (fdctrl_t *fdctrl);

static uint32_t fdctrl_read_statusB (fdctrl_t *fdctrl);
static uint32_t fdctrl_read_dor (fdctrl_t *fdctrl);
static void fdctrl_write_dor (fdctrl_t *fdctrl, uint32_t value);
static uint32_t fdctrl_read_tape (fdctrl_t *fdctrl);
static void fdctrl_write_tape (fdctrl_t *fdctrl, uint32_t value);
static uint32_t fdctrl_read_main_status (fdctrl_t *fdctrl);
static void fdctrl_write_rate (fdctrl_t *fdctrl, uint32_t value);
static uint32_t fdctrl_read_data (fdctrl_t *fdctrl);
static void fdctrl_write_data (fdctrl_t *fdctrl, uint32_t value);
static uint32_t fdctrl_read_dir (fdctrl_t *fdctrl);

enum {
    FD_DIR_WRITE   = 0,
    FD_DIR_READ    = 1,
    FD_DIR_SCANE   = 2,
    FD_DIR_SCANL   = 3,
    FD_DIR_SCANH   = 4,
};

enum {

    FD_STATE_MULTI  = 0x01,	/* multi track flag */
    FD_STATE_FORMAT = 0x02,	/* format flag */
    FD_STATE_SEEK   = 0x04,	/* seek flag */

};

enum {

    FD_REG_SRA = 0x00,
    FD_REG_SRB = 0x01,

    FD_REG_DOR = 0x02,
    FD_REG_TDR = 0x03,
    FD_REG_MSR = 0x04,
    FD_REG_DSR = 0x04,
    FD_REG_FIFO = 0x05,
    FD_REG_DIR = 0x07,
};

enum {

    FD_CMD_READ_TRACK = 0x02,

    FD_CMD_SPECIFY = 0x03,
    FD_CMD_SENSE_DRIVE_STATUS = 0x04,

    FD_CMD_WRITE = 0x05,
    FD_CMD_READ = 0x06,

    FD_CMD_RECALIBRATE = 0x07,
    FD_CMD_SENSE_INTERRUPT_STATUS = 0x08,

    FD_CMD_WRITE_DELETED = 0x09,
    FD_CMD_READ_ID = 0x0a,
    FD_CMD_READ_DELETED = 0x0c,
    FD_CMD_FORMAT_TRACK = 0x0d,

    FD_CMD_DUMPREG = 0x0e,
    FD_CMD_SEEK = 0x0f,
    FD_CMD_VERSION = 0x10,

    FD_CMD_SCAN_EQUAL = 0x11,

    FD_CMD_PERPENDICULAR_MODE = 0x12,
    FD_CMD_CONFIGURE = 0x13,

    FD_CMD_LOCK = 0x14,
    FD_CMD_VERIFY = 0x16,

    FD_CMD_POWERDOWN_MODE = 0x17,
    FD_CMD_PART_ID = 0x18,

    FD_CMD_SCAN_LOW_OR_EQUAL = 0x19,
    FD_CMD_SCAN_HIGH_OR_EQUAL = 0x1d,

    FD_CMD_SAVE = 0x2c,
    FD_CMD_OPTION = 0x33,
    FD_CMD_RESTORE = 0x4c,
    FD_CMD_DRIVE_SPECIFICATION_COMMAND = 0x8e,
    FD_CMD_RELATIVE_SEEK_OUT = 0x8f,
    FD_CMD_FORMAT_AND_WRITE = 0xcd,
    FD_CMD_RELATIVE_SEEK_IN = 0xcf,
};

enum {
    FD_CONFIG_PRETRK = 0xff, /* Pre-compensation set to track 0 */
    FD_CONFIG_FIFOTHR = 0x0f, /* FIFO threshold set to 1 byte */
    FD_CONFIG_POLL  = 0x10, /* Poll enabled */
    FD_CONFIG_EFIFO = 0x20, /* FIFO disabled */
    FD_CONFIG_EIS   = 0x40, /* No implied seeks */
};

enum {
    FD_SR0_EQPMT    = 0x10,
    FD_SR0_SEEK     = 0x20,
    FD_SR0_ABNTERM  = 0x40,
    FD_SR0_INVCMD   = 0x80,
    FD_SR0_RDYCHG   = 0xc0,
};

enum {

    FD_SR1_EC       = 0x80, /* End of cylinder */
};

enum {
    FD_SR2_SNS      = 0x04, /* Scan not satisfied */
    FD_SR2_SEH      = 0x08, /* Scan equal hit */
};

enum {

    FD_SRA_DIR      = 0x01,
    FD_SRA_nWP      = 0x02,
    FD_SRA_nINDX    = 0x04,
    FD_SRA_HDSEL    = 0x08,
    FD_SRA_nTRK0    = 0x10,
    FD_SRA_STEP     = 0x20,
    FD_SRA_nDRV2    = 0x40,
    FD_SRA_INTPEND  = 0x80,
};

enum {
    FD_SRB_MTR0     = 0x01,
    FD_SRB_MTR1     = 0x02,
    FD_SRB_WGATE    = 0x04,
    FD_SRB_RDATA    = 0x08,
    FD_SRB_WDATA    = 0x10,
    FD_SRB_DR0      = 0x20,
};

enum {

#if MAX_FD == 4
    FD_DOR_SELMASK  = 0x03,
#else

    FD_DOR_SELMASK  = 0x01,

#endif

    FD_DOR_nRESET   = 0x04,
    FD_DOR_DMAEN    = 0x08,
    FD_DOR_MOTEN0   = 0x10,
    FD_DOR_MOTEN1   = 0x20,
    FD_DOR_MOTEN2   = 0x40,
    FD_DOR_MOTEN3   = 0x80,
};

enum {

#if MAX_FD == 4

    FD_TDR_BOOTSEL  = 0x0c,

#else
    FD_TDR_BOOTSEL  = 0x04,
#endif

};

enum {
    FD_DSR_DRATEMASK= 0x03,
    FD_DSR_PWRDOWN  = 0x40,
    FD_DSR_SWRESET  = 0x80,
};

enum {
    FD_MSR_DRV0BUSY = 0x01,
    FD_MSR_DRV1BUSY = 0x02,
    FD_MSR_DRV2BUSY = 0x04,
    FD_MSR_DRV3BUSY = 0x08,
    FD_MSR_CMDBUSY  = 0x10,
    FD_MSR_NONDMA   = 0x20,
    FD_MSR_DIO      = 0x40,
    FD_MSR_RQM      = 0x80,
};

enum {
    FD_DIR_DSKCHG   = 0x80,
};

#define FD_MULTI_TRACK(state) ((state) & FD_STATE_MULTI)
#define FD_DID_SEEK(state) ((state) & FD_STATE_SEEK)

#define FD_FORMAT_CMD(state) ((state) & FD_STATE_FORMAT)

struct fdctrl_t {

    SysBusDevice busdev;

    /* Controller's identification */

    uint8_t version;
    /* HW */

    qemu_irq irq;

    int dma_chann;

    /* Controller state */

    QEMUTimer *result_timer;

    uint8_t sra;
    uint8_t srb;

    uint8_t dor;

    uint8_t tdr;

    uint8_t dsr;

    uint8_t msr;

    uint8_t cur_drv;

    uint8_t status0;
    uint8_t status1;
    uint8_t status2;

    /* Command FIFO */

    uint8_t *fifo;

    uint32_t data_pos;
    uint32_t data_len;
    uint8_t data_state;
    uint8_t data_dir;

    uint8_t eot; /* last wanted sector */

    /* States kept only to be returned back */
    /* Timers state */
    uint8_t timer0;
    uint8_t timer1;
    /* precompensation */
    uint8_t precomp_trk;
    uint8_t config;
    uint8_t lock;
    /* Power down config (also with status regB access mode */
    uint8_t pwrd;

    /* Sun4m quirks? */

    int sun4m;

    /* Floppy drives */

    fdrive_t drives[MAX_FD];

    int reset_sensei;

};

static uint32_t fdctrl_read (void *opaque, uint32_t reg)
{
    fdctrl_t *fdctrl = opaque;
    uint32_t retval;

    switch (reg) {

    case FD_REG_SRA:
        retval = fdctrl_read_statusA(fdctrl);

        break;

    case FD_REG_SRB:

        retval = fdctrl_read_statusB(fdctrl);
        break;

    case FD_REG_DOR:

        retval = fdctrl_read_dor(fdctrl);
        break;

    case FD_REG_TDR:

        retval = fdctrl_read_tape(fdctrl);

        break;

    case FD_REG_MSR:

        retval = fdctrl_read_main_status(fdctrl);

        break;

    case FD_REG_FIFO:

        retval = fdctrl_read_data(fdctrl);

        break;

    case FD_REG_DIR:

        retval = fdctrl_read_dir(fdctrl);

        break;

    default:

        retval = (uint32_t)(-1);
        break;

    }

    FLOPPY_DPRINTF("read reg%d: 0x%02x\n", reg & 7, retval);

    return retval;
}

static void fdctrl_write (void *opaque, uint32_t reg, uint32_t value)
{
    fdctrl_t *fdctrl = opaque;

    FLOPPY_DPRINTF("write reg%d: 0x%02x\n", reg & 7, value);

    switch (reg) {

    case FD_REG_DOR:

        fdctrl_write_dor(fdctrl, value);
        break;

    case FD_REG_TDR:

        fdctrl_write_tape(fdctrl, value);

        break;

    case FD_REG_DSR:

        fdctrl_write_rate(fdctrl, value);

        break;

    case FD_REG_FIFO:

        fdctrl_write_data(fdctrl, value);

        break;

    default:

        break;

    }

}

static uint32_t fdctrl_read_port (void *opaque, uint32_t reg)
{
    return fdctrl_read(opaque, reg & 7);
}

static void fdctrl_write_port (void *opaque, uint32_t reg, uint32_t value)
{
    fdctrl_write(opaque, reg & 7, value);
}

static uint32_t fdctrl_read_mem (void *opaque, target_phys_addr_t reg)
{

    return fdctrl_read(opaque, (uint32_t)reg);

}

static void fdctrl_write_mem (void *opaque,

                              target_phys_addr_t reg, uint32_t value)
{

    fdctrl_write(opaque, (uint32_t)reg, value);

}

static CPUReadMemoryFunc *fdctrl_mem_read[3] = {

    fdctrl_read_mem,
    fdctrl_read_mem,
    fdctrl_read_mem,

};

static CPUWriteMemoryFunc *fdctrl_mem_write[3] = {

    fdctrl_write_mem,
    fdctrl_write_mem,
    fdctrl_write_mem,

};

static CPUReadMemoryFunc *fdctrl_mem_read_strict[3] = {
    fdctrl_read_mem,
    NULL,
    NULL,
};

static CPUWriteMemoryFunc *fdctrl_mem_write_strict[3] = {
    fdctrl_write_mem,
    NULL,
    NULL,
};

static void fd_save (QEMUFile *f, fdrive_t *fd)
{
    qemu_put_8s(f, &fd->head);
    qemu_put_8s(f, &fd->track);
    qemu_put_8s(f, &fd->sect);
}

static void fdc_save (QEMUFile *f, void *opaque)
{
    fdctrl_t *s = opaque;

    uint8_t tmp;
    int i;

    uint8_t dor = s->dor | GET_CUR_DRV(s);

    /* Controller state */
    qemu_put_8s(f, &s->sra);
    qemu_put_8s(f, &s->srb);

    qemu_put_8s(f, &dor);

    qemu_put_8s(f, &s->tdr);

    qemu_put_8s(f, &s->dsr);
    qemu_put_8s(f, &s->msr);
    qemu_put_8s(f, &s->status0);
    qemu_put_8s(f, &s->status1);
    qemu_put_8s(f, &s->status2);
    /* Command FIFO */

    qemu_put_buffer(f, s->fifo, FD_SECTOR_LEN);
    qemu_put_be32s(f, &s->data_pos);
    qemu_put_be32s(f, &s->data_len);
    qemu_put_8s(f, &s->data_state);
    qemu_put_8s(f, &s->data_dir);
    qemu_put_8s(f, &s->eot);

    /* States kept only to be returned back */

    qemu_put_8s(f, &s->timer0);
    qemu_put_8s(f, &s->timer1);
    qemu_put_8s(f, &s->precomp_trk);
    qemu_put_8s(f, &s->config);
    qemu_put_8s(f, &s->lock);
    qemu_put_8s(f, &s->pwrd);

    tmp = MAX_FD;
    qemu_put_8s(f, &tmp);
    for (i = 0; i < MAX_FD; i++)
        fd_save(f, &s->drives[i]);

}

static int fd_load (QEMUFile *f, fdrive_t *fd)
{
    qemu_get_8s(f, &fd->head);
    qemu_get_8s(f, &fd->track);
    qemu_get_8s(f, &fd->sect);

    return 0;
}

static int fdc_load (QEMUFile *f, void *opaque, int version_id)
{
    fdctrl_t *s = opaque;

    int i, ret = 0;
    uint8_t n;

    if (version_id != 2)

        return -EINVAL;

    /* Controller state */
    qemu_get_8s(f, &s->sra);
    qemu_get_8s(f, &s->srb);

    qemu_get_8s(f, &s->dor);
    SET_CUR_DRV(s, s->dor & FD_DOR_SELMASK);
    s->dor &= ~FD_DOR_SELMASK;

    qemu_get_8s(f, &s->tdr);

    qemu_get_8s(f, &s->dsr);
    qemu_get_8s(f, &s->msr);
    qemu_get_8s(f, &s->status0);
    qemu_get_8s(f, &s->status1);
    qemu_get_8s(f, &s->status2);
    /* Command FIFO */

    qemu_get_buffer(f, s->fifo, FD_SECTOR_LEN);
    qemu_get_be32s(f, &s->data_pos);
    qemu_get_be32s(f, &s->data_len);
    qemu_get_8s(f, &s->data_state);
    qemu_get_8s(f, &s->data_dir);
    qemu_get_8s(f, &s->eot);

    /* States kept only to be returned back */

    qemu_get_8s(f, &s->timer0);
    qemu_get_8s(f, &s->timer1);
    qemu_get_8s(f, &s->precomp_trk);
    qemu_get_8s(f, &s->config);
    qemu_get_8s(f, &s->lock);
    qemu_get_8s(f, &s->pwrd);