Archipelago » qemu

/*

 * QEMU Floppy disk emulator

 * 

 * Copyright (c) 2003 Jocelyn Mayer

 * 

 * 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.

 */

#include "vl.h"

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

/* debug Floppy devices */

//#define DEBUG_FLOPPY

#ifdef DEBUG_FLOPPY

#define FLOPPY_DPRINTF(fmt, args...) \

do { printf("FLOPPY: " fmt , ##args); } while (0)

#else

#define FLOPPY_DPRINTF(fmt, args...)

#endif

#define FLOPPY_ERROR(fmt, args...) \

do { printf("FLOPPY ERROR: %s: " fmt, __func__ , ##args); } while (0)

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

/* Floppy drive emulation                               */

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

#define FD_SECTOR_LEN 512

#define FD_SECTOR_SC  2   /* Sector size code */

/* 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 fdrive_flags_t {

    FDRIVE_MOTOR_ON   = 0x01, /* motor on/off           */

    FDRIVE_REVALIDATE = 0x02, /* Revalidated            */

} fdrive_flags_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;

    fdrive_flags_t drflags;

    uint8_t perpendicular;    /* 2.88 MB access mode    */

    /* Position */

    uint8_t head;

    uint8_t track;

    uint8_t sect;

    /* Last operation status */

    uint8_t dir;              /* Direction              */

    uint8_t rw;               /* Read/write             */

    /* 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;

    if (bs)

        drv->drive = FDRIVE_DRV_144;

    else

        drv->drive = FDRIVE_DRV_NONE;

    drv->drflags = 0;

    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);

}

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_ERROR("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_ERROR("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;

    drv->dir = 1;

    drv->rw = 0;

}

/* 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 unsigned char *str;

} fd_format_t;

static 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)

{

    fd_format_t *parse;

    int64_t nb_sectors, size;

    int i, first_match, match;

    int nb_heads, max_track, last_sect, ro;

    FLOPPY_DPRINTF("revalidate\n");

    drv->drflags &= ~FDRIVE_REVALIDATE;

    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) {

            printf("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;

            printf("%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 {

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

        drv->last_sect = 0;

        drv->max_track = 0;

        drv->flags &= ~FDISK_DBL_SIDES;

    }

    drv->drflags |= FDRIVE_REVALIDATE;

}

/* Motor control */

static void fd_start (fdrive_t *drv)

{

    drv->drflags |= FDRIVE_MOTOR_ON;

}

static void fd_stop (fdrive_t *drv)

{

    drv->drflags &= ~FDRIVE_MOTOR_ON;

}

/* Re-initialise a drives (motor off, repositioned) */

static void fd_reset (fdrive_t *drv)

{

    fd_stop(drv);

    fd_recalibrate(drv);

}

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

/* Intel 82078 floppy disk controler 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, target_ulong addr, int size);

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

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_CTRL_ACTIVE = 0x01,

    FD_CTRL_RESET  = 0x02,

    FD_CTRL_SLEEP  = 0x04,

    FD_CTRL_BUSY   = 0x08,

    FD_CTRL_INTR   = 0x10,

};

enum {

    FD_DIR_WRITE   = 0,

    FD_DIR_READ    = 1,

    FD_DIR_SCANE   = 2,

    FD_DIR_SCANL   = 3,

    FD_DIR_SCANH   = 4,

};

enum {

    FD_STATE_CMD    = 0x00,

    FD_STATE_STATUS = 0x01,

    FD_STATE_DATA   = 0x02,

    FD_STATE_STATE  = 0x03,

    FD_STATE_MULTI  = 0x10,

    FD_STATE_SEEK   = 0x20,

    FD_STATE_FORMAT = 0x40,

};

#define FD_STATE(state) ((state) & FD_STATE_STATE)

#define FD_SET_STATE(state, new_state) \

do { (state) = ((state) & ~FD_STATE_STATE) | (new_state); } while (0)

#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 {

    fdctrl_t *fdctrl;

    /* Controler's identification */

    uint8_t version;

    /* HW */

    int irq_lvl;

    int dma_chann;

    uint32_t io_base;

    /* Controler state */

    uint8_t state;

    uint8_t dma_en;

    uint8_t cur_drv;

    uint8_t bootsel;

    /* Command FIFO */

    uint8_t fifo[FD_SECTOR_LEN];

    uint32_t data_pos;

    uint32_t data_len;

    uint8_t data_state;

    uint8_t data_dir;

    uint8_t int_status;

    /* 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;

    /* Floppy drives */

    fdrive_t drives[2];

};

static uint32_t fdctrl_read (void *opaque, uint32_t reg)

{

    fdctrl_t *fdctrl = opaque;

    uint32_t retval;

    switch (reg & 0x07) {

    case 0x01:

        retval = fdctrl_read_statusB(fdctrl);

        break;

    case 0x02:

        retval = fdctrl_read_dor(fdctrl);

        break;

    case 0x03:

        retval = fdctrl_read_tape(fdctrl);

        break;

    case 0x04:

        retval = fdctrl_read_main_status(fdctrl);

        break;

    case 0x05:

        retval = fdctrl_read_data(fdctrl);

        break;

    case 0x07:

        retval = fdctrl_read_dir(fdctrl);

        break;

    default:

        retval = (uint32_t)(-1);

        break;

    }

    return retval;

}

static void fdctrl_write (void *opaque, uint32_t reg, uint32_t value)

{

    fdctrl_t *fdctrl = opaque;

    switch (reg & 0x07) {

    case 0x02:

        fdctrl_write_dor(fdctrl, value);

        break;

    case 0x03:

        fdctrl_write_tape(fdctrl, value);

        break;

    case 0x04:

        fdctrl_write_rate(fdctrl, value);

        break;

    case 0x05:

        fdctrl_write_data(fdctrl, value);

        break;

    default:

        break;

    }

}

static void fd_change_cb (void *opaque)

{

    fdrive_t *drv = opaque;

    FLOPPY_DPRINTF("disk change\n");

    fd_revalidate(drv);

#if 0

    fd_recalibrate(drv);

    fdctrl_reset_fifo(drv->fdctrl);

    fdctrl_raise_irq(drv->fdctrl, 0x20);

#endif

}

fdctrl_t *fdctrl_init (int irq_lvl, int dma_chann, int mem_mapped, 

                       uint32_t io_base,

                       BlockDriverState **fds)

{

    fdctrl_t *fdctrl;

//    int io_mem;

    int i;

    FLOPPY_DPRINTF("init controler\n");

    fdctrl = qemu_mallocz(sizeof(fdctrl_t));

    if (!fdctrl)

        return NULL;

    fdctrl->version = 0x90; /* Intel 82078 controler */

    fdctrl->irq_lvl = irq_lvl;

    fdctrl->dma_chann = dma_chann;

    fdctrl->io_base = io_base;

    fdctrl->config = 0x60; /* Implicit seek, polling & FIFO enabled */

    if (fdctrl->dma_chann != -1) {

        fdctrl->dma_en = 1;

        DMA_register_channel(dma_chann, &fdctrl_transfer_handler, fdctrl);

    } else {

        fdctrl->dma_en = 0;

    }

    for (i = 0; i < 2; i++) {

        fd_init(&fdctrl->drives[i], fds[i]);

        if (fds[i]) {

            bdrv_set_change_cb(fds[i],

                               &fd_change_cb, &fdctrl->drives[i]);

        }

    }

    fdctrl_reset(fdctrl, 0);

    fdctrl->state = FD_CTRL_ACTIVE;

    if (mem_mapped) {

        FLOPPY_ERROR("memory mapped floppy not supported by now !\n");

#if 0

        io_mem = cpu_register_io_memory(0, fdctrl_mem_read, fdctrl_mem_write);

        cpu_register_physical_memory(base, 0x08, io_mem);

#endif

    } else {

        register_ioport_read(io_base + 0x01, 5, 1, &fdctrl_read, fdctrl);

        register_ioport_read(io_base + 0x07, 1, 1, &fdctrl_read, fdctrl);

        register_ioport_write(io_base + 0x01, 5, 1, &fdctrl_write, fdctrl);

        register_ioport_write(io_base + 0x07, 1, 1, &fdctrl_write, fdctrl);

    }

    for (i = 0; i < 2; i++) {

        fd_revalidate(&fdctrl->drives[i]);

    }

    return fdctrl;

}

/* XXX: may change if moved to bdrv */

int fdctrl_get_drive_type(fdctrl_t *fdctrl, int drive_num)

{

    return fdctrl->drives[drive_num].drive;

}

/* Change IRQ state */

static void fdctrl_reset_irq (fdctrl_t *fdctrl)

{

    if (fdctrl->state & FD_CTRL_INTR) {

        pic_set_irq(fdctrl->irq_lvl, 0);

        fdctrl->state &= ~(FD_CTRL_INTR | FD_CTRL_SLEEP | FD_CTRL_BUSY);

    }

}

static void fdctrl_raise_irq (fdctrl_t *fdctrl, uint8_t status)

{

    if (~(fdctrl->state & FD_CTRL_INTR)) {

        pic_set_irq(fdctrl->irq_lvl, 1);

        fdctrl->state |= FD_CTRL_INTR;

    }

    FLOPPY_DPRINTF("Set interrupt status to 0x%02x\n", status);

    fdctrl->int_status = status;

}

/* Reset controler */

static void fdctrl_reset (fdctrl_t *fdctrl, int do_irq)

{

    int i;

    FLOPPY_DPRINTF("reset controler\n");

    fdctrl_reset_irq(fdctrl);

    /* Initialise controler */

    fdctrl->cur_drv = 0;

    /* FIFO state */

    fdctrl->data_pos = 0;

    fdctrl->data_len = 0;

    fdctrl->data_state = FD_STATE_CMD;

    fdctrl->data_dir = FD_DIR_WRITE;

    for (i = 0; i < MAX_FD; i++)

        fd_reset(&fdctrl->drives[i]);

    fdctrl_reset_fifo(fdctrl);

    if (do_irq)

        fdctrl_raise_irq(fdctrl, 0x20);

}

static inline fdrive_t *drv0 (fdctrl_t *fdctrl)

{

    return &fdctrl->drives[fdctrl->bootsel];

}

static inline fdrive_t *drv1 (fdctrl_t *fdctrl)

{

    return &fdctrl->drives[1 - fdctrl->bootsel];

}

static fdrive_t *get_cur_drv (fdctrl_t *fdctrl)

{

    return fdctrl->cur_drv == 0 ? drv0(fdctrl) : drv1(fdctrl);

}

/* Status B register : 0x01 (read-only) */

static uint32_t fdctrl_read_statusB (fdctrl_t *fdctrl)

{

    fdctrl_reset_irq(fdctrl);

    FLOPPY_DPRINTF("status register: 0x00\n");

    return 0;

}

/* Digital output register : 0x02 */

static uint32_t fdctrl_read_dor (fdctrl_t *fdctrl)

{

    uint32_t retval = 0;

    /* Drive motors state indicators */

    if (drv0(fdctrl)->drflags & FDRIVE_MOTOR_ON)

        retval |= 1 << 5;

    if (drv1(fdctrl)->drflags & FDRIVE_MOTOR_ON)

        retval |= 1 << 4;

    /* DMA enable */

    retval |= fdctrl->dma_en << 3;

    /* Reset indicator */

    retval |= (fdctrl->state & FD_CTRL_RESET) == 0 ? 0x04 : 0;

    /* Selected drive */

    retval |= fdctrl->cur_drv;

    FLOPPY_DPRINTF("digital output register: 0x%02x\n", retval);

    return retval;

}

static void fdctrl_write_dor (fdctrl_t *fdctrl, uint32_t value)

{

    fdctrl_reset_irq(fdctrl);

    /* Reset mode */

    if (fdctrl->state & FD_CTRL_RESET) {

        if (!(value & 0x04)) {

            FLOPPY_DPRINTF("Floppy controler in RESET state !\n");

            return;

        }

    }

    FLOPPY_DPRINTF("digital output register set to 0x%02x\n", value);

    /* Drive motors state indicators */

    if (value & 0x20)

        fd_start(drv1(fdctrl));

    else

        fd_stop(drv1(fdctrl));

    if (value & 0x10)

        fd_start(drv0(fdctrl));

    else

        fd_stop(drv0(fdctrl));

    /* DMA enable */

#if 0

    if (fdctrl->dma_chann != -1)

        fdctrl->dma_en = 1 - ((value >> 3) & 1);

#endif

    /* Reset */

    if (!(value & 0x04)) {

        if (!(fdctrl->state & FD_CTRL_RESET)) {

            FLOPPY_DPRINTF("controler enter RESET state\n");

            fdctrl->state |= FD_CTRL_RESET;

            fdctrl_reset(fdctrl, 1);

        }

    } else {

        if (fdctrl->state & FD_CTRL_RESET) {

            FLOPPY_DPRINTF("controler out of RESET state\n");

            fdctrl->state &= ~(FD_CTRL_RESET | FD_CTRL_SLEEP);

        }

    }

    /* Selected drive */

    fdctrl->cur_drv = value & 1;

}

/* Tape drive register : 0x03 */

static uint32_t fdctrl_read_tape (fdctrl_t *fdctrl)

{

    uint32_t retval = 0;

    fdctrl_reset_irq(fdctrl);

    /* Disk boot selection indicator */

    retval |= fdctrl->bootsel << 2;

    /* Tape indicators: never allowed */

    FLOPPY_DPRINTF("tape drive register: 0x%02x\n", retval);

    return retval;

}

static void fdctrl_write_tape (fdctrl_t *fdctrl, uint32_t value)

{

    fdctrl_reset_irq(fdctrl);

    /* Reset mode */

    if (fdctrl->state & FD_CTRL_RESET) {

        FLOPPY_DPRINTF("Floppy controler in RESET state !\n");

        return;

    }

    FLOPPY_DPRINTF("tape drive register set to 0x%02x\n", value);

    /* Disk boot selection indicator */

    fdctrl->bootsel = (value >> 2) & 1;

    /* Tape indicators: never allow */

}

/* Main status register : 0x04 (read) */

static uint32_t fdctrl_read_main_status (fdctrl_t *fdctrl)

{

    uint32_t retval = 0;

    fdctrl_reset_irq(fdctrl);

    fdctrl->state &= ~(FD_CTRL_SLEEP | FD_CTRL_RESET);

    if (!(fdctrl->state & FD_CTRL_BUSY)) {

        /* Data transfer allowed */

        retval |= 0x80;

        /* Data transfer direction indicator */

        if (fdctrl->data_dir == FD_DIR_READ)

            retval |= 0x40;

    }

    /* Should handle 0x20 for SPECIFY command */

    /* Command busy indicator */

    if (FD_STATE(fdctrl->data_state) == FD_STATE_DATA ||

        FD_STATE(fdctrl->data_state) == FD_STATE_STATUS)

        retval |= 0x10;

    FLOPPY_DPRINTF("main status register: 0x%02x\n", retval);

    return retval;

}

/* Data select rate register : 0x04 (write) */

static void fdctrl_write_rate (fdctrl_t *fdctrl, uint32_t value)

{

    fdctrl_reset_irq(fdctrl);

    /* Reset mode */

    if (fdctrl->state & FD_CTRL_RESET) {

            FLOPPY_DPRINTF("Floppy controler in RESET state !\n");

            return;

        }

    FLOPPY_DPRINTF("select rate register set to 0x%02x\n", value);

    /* Reset: autoclear */

    if (value & 0x80) {

        fdctrl->state |= FD_CTRL_RESET;

        fdctrl_reset(fdctrl, 1);

        fdctrl->state &= ~FD_CTRL_RESET;

    }

    if (value & 0x40) {

        fdctrl->state |= FD_CTRL_SLEEP;

        fdctrl_reset(fdctrl, 1);

    }

//        fdctrl.precomp = (value >> 2) & 0x07;

}

/* Digital input register : 0x07 (read-only) */

static uint32_t fdctrl_read_dir (fdctrl_t *fdctrl)

{

    uint32_t retval = 0;

    fdctrl_reset_irq(fdctrl);

    if (drv0(fdctrl)->drflags & FDRIVE_REVALIDATE ||

        drv1(fdctrl)->drflags & FDRIVE_REVALIDATE)

        retval |= 0x80;

    if (retval != 0)

        FLOPPY_DPRINTF("Floppy digital input register: 0x%02x\n", retval);

    drv0(fdctrl)->drflags &= ~FDRIVE_REVALIDATE;

    drv1(fdctrl)->drflags &= ~FDRIVE_REVALIDATE;

    return retval;

}

/* FIFO state control */

static void fdctrl_reset_fifo (fdctrl_t *fdctrl)

{

    fdctrl->data_dir = FD_DIR_WRITE;

    fdctrl->data_pos = 0;

    FD_SET_STATE(fdctrl->data_state, FD_STATE_CMD);

}

/* Set FIFO status for the host to read */

static void fdctrl_set_fifo (fdctrl_t *fdctrl, int fifo_len, int do_irq)

{

    fdctrl->data_dir = FD_DIR_READ;

    fdctrl->data_len = fifo_len;

    fdctrl->data_pos = 0;

    FD_SET_STATE(fdctrl->data_state, FD_STATE_STATUS);

    if (do_irq)

        fdctrl_raise_irq(fdctrl, 0x00);

}

/* Set an error: unimplemented/unknown command */

static void fdctrl_unimplemented (fdctrl_t *fdctrl)

{

#if 0

    fdrive_t *cur_drv;

    cur_drv = get_cur_drv(fdctrl);

    fdctrl->fifo[0] = 0x60 | (cur_drv->head << 1) | fdctrl->cur_drv;

    fdctrl->fifo[1] = 0x00;

    fdctrl->fifo[2] = 0x00;

    fdctrl_set_fifo(fdctrl, 3, 1);

#else

    //    fdctrl_reset_fifo(fdctrl);

    fdctrl->fifo[0] = 0x80;

    fdctrl_set_fifo(fdctrl, 1, 0);

#endif

}

/* Callback for transfer end (stop or abort) */

static void fdctrl_stop_transfer (fdctrl_t *fdctrl, uint8_t status0,

                                  uint8_t status1, uint8_t status2)

{

    fdrive_t *cur_drv;

    cur_drv = get_cur_drv(fdctrl);

    FLOPPY_DPRINTF("transfer status: %02x %02x %02x (%02x)\n",

                   status0, status1, status2,

                   status0 | (cur_drv->head << 1) | fdctrl->cur_drv);

    fdctrl->fifo[0] = status0 | (cur_drv->head << 1) | fdctrl->cur_drv;

    fdctrl->fifo[1] = status1;

    fdctrl->fifo[2] = status2;

    fdctrl->fifo[3] = cur_drv->track;

    fdctrl->fifo[4] = cur_drv->head;

    fdctrl->fifo[5] = cur_drv->sect;

    fdctrl->fifo[6] = FD_SECTOR_SC;

    fdctrl->data_dir = FD_DIR_READ;

    if (fdctrl->state & FD_CTRL_BUSY)

        DMA_release_DREQ(fdctrl->dma_chann);

    fdctrl_set_fifo(fdctrl, 7, 1);

}

/* Prepare a data transfer (either DMA or FIFO) */

static void fdctrl_start_transfer (fdctrl_t *fdctrl, int direction)

{

    fdrive_t *cur_drv;

    uint8_t kh, kt, ks;

    int did_seek;

    fdctrl->cur_drv = fdctrl->fifo[1] & 1;

    cur_drv = get_cur_drv(fdctrl);

    kt = fdctrl->fifo[2];

    kh = fdctrl->fifo[3];

    ks = fdctrl->fifo[4];

    FLOPPY_DPRINTF("Start tranfert at %d %d %02x %02x (%d)\n",

                   fdctrl->cur_drv, kh, kt, ks,

                   _fd_sector(kh, kt, ks, cur_drv->last_sect));

    did_seek = 0;

    switch (fd_seek(cur_drv, kh, kt, ks, fdctrl->config & 0x40)) {

    case 2:

        /* sect too big */

        fdctrl_stop_transfer(fdctrl, 0x40, 0x00, 0x00);

        fdctrl->fifo[3] = kt;

        fdctrl->fifo[4] = kh;

        fdctrl->fifo[5] = ks;

        return;

    case 3:

        /* track too big */

        fdctrl_stop_transfer(fdctrl, 0x40, 0x80, 0x00);

        fdctrl->fifo[3] = kt;

        fdctrl->fifo[4] = kh;

        fdctrl->fifo[5] = ks;

        return;

    case 4:

        /* No seek enabled */

        fdctrl_stop_transfer(fdctrl, 0x40, 0x00, 0x00);

        fdctrl->fifo[3] = kt;

        fdctrl->fifo[4] = kh;

        fdctrl->fifo[5] = ks;

        return;

    case 1:

        did_seek = 1;

        break;

    default:

        break;

    }

    /* Set the FIFO state */

    fdctrl->data_dir = direction;

    fdctrl->data_pos = 0;

    FD_SET_STATE(fdctrl->data_state, FD_STATE_DATA); /* FIFO ready for data */

    if (fdctrl->fifo[0] & 0x80)

        fdctrl->data_state |= FD_STATE_MULTI;

    else

        fdctrl->data_state &= ~FD_STATE_MULTI;

    if (did_seek)

        fdctrl->data_state |= FD_STATE_SEEK;