quickdev16/snes/fatfstest/diskio.c

#include "integer.h"
#include "diskio.h"
#include "config.h"
#include "data.h"
#include "debug.h"



/*
 * Interface ** Scratch Buffer addr 3 byte size 1 byte
 * 
 * ** Call Interface cmd 1 byte sector 4 bytes count 1 byte return 1 byte
 * 
 * ** Commands * disk_init * disk_read * disk_write 
 */

/*-----------------------------------------------------------------------*/
/*
 * Initialize Disk Drive 
 */
/*-----------------------------------------------------------------------*/

#include <string.h>


// TODO: Figure out gobal vars ?!?

DSTATUS Stat = 0;               // STA_NOINIT; /* Disk status */


DSTATUS disk_initialize(BYTE drv)
{

    byte retval;
#ifdef MMIO_DEBUG
    printfc("SNES::disk_initialize: called drv=%i stat=%i\n", drv, Stat);
#endif
    if (drv)
        return STA_NOINIT;      /* Supports only single drive */
    Stat |= STA_NOINIT;
#ifdef MMIO_DEBUG
    printfc("SNES::disk_initialize: stat=%i\n", Stat);
#endif
    *(byte *) MMIO_RETVAL = STA_VOID;
    *(byte *) MMIO_CMD = CMD_INIT;
#ifdef MMIO_DEBUG
    printfc("SNES::disk_initialize: poll retval\n");
#endif
    while ((retval = *(byte *) MMIO_RETVAL) == STA_VOID);
    Stat &= ~STA_NOINIT;        /* When device goes ready, clear STA_NOINIT */
#ifdef MMIO_DEBUG
    printfc("SNES::disk_initialize: done Stat=%i\n", Stat);
#endif
    return Stat;
}


/*-----------------------------------------------------------------------*/
/*
 * Return Disk Status 
 */
/*-----------------------------------------------------------------------*/

DSTATUS disk_status(BYTE drv)
{
    if (drv)
        return STA_NOINIT;      /* Supports only single drive */
    return Stat;
}


/*-----------------------------------------------------------------------*/
/*
 * Read Sector(s) 
 */
/*-----------------------------------------------------------------------*/

DRESULT disk_read(BYTE drv,     /* Physical drive nmuber (0) */
                  BYTE * buff,  /* Data buffer to store read data */
                  DWORD sector, /* Sector number (LBA) */
                  BYTE count    /* Sector count (1..255) */
    )
{
    DWORD offset;
    INT size;
    byte retval;
    word i;

#ifdef MMIO_DEBUG
    printfc("SNES::disk_read: sector=%li count=%i\n", sector, count);
#endif
    if (drv || !count)
        return RES_PARERR;
#ifdef MMIO_DEBUG
    printfc("SNES::disk_read: drv ok\n");
#endif
    if (Stat & STA_NOINIT)
        return RES_NOTRDY;
#ifdef MMIO_DEBUG
    printfc("SNES::disk_read: sta ok\n");
#endif

    *(byte *) MMIO_RETVAL = STA_VOID;
    *(byte *) MMIO_CMD = CMD_READ;

    *(byte *) MMIO_SECTOR01 = (sector >> 24) & 0xff;
    *(byte *) MMIO_SECTOR02 = (sector >> 16) & 0xff;
    *(byte *) MMIO_SECTOR03 = (sector >> 8) & 0xff;
    *(byte *) MMIO_SECTOR04 = (sector) & 0xff;

    *(byte *) MMIO_COUNT = count;

#ifdef MMIO_DEBUG
    printfc("SNES::disk_read: poll retval\n");
#endif
    while ((retval = *(byte *) MMIO_RETVAL) == STA_VOID);


#ifdef MMIO_DEBUG
    printfc("SNES::disk_read: copy buffer to %lx\n", SHARED_ADDR);
#endif
    for (i = 0; i < (count * 512); i++) {
        buff[i] = *(byte *) (SHARED_ADDR + i);
#ifdef MMIO_DEBUG
        if (i < 4)
            printfc("0x%x ", buff[i]);
#endif
    }
#ifdef MMIO_DEBUG
    printfc("\n");
#endif
    return retval;
}



/*-----------------------------------------------------------------------*/
/*
 * Write Sector(s) 
 */
/*-----------------------------------------------------------------------*/

#if _READONLY == 0
DRESULT disk_write(BYTE drv,    /* Physical drive nmuber (0) */
                   const BYTE * buff,   /* Data to be written */
                   DWORD sector,        /* Sector number (LBA) */
                   BYTE count   /* Sector count (1..255) */
    )
{
    DWORD offset;
    INT size;

    if (drv || !count)
        return RES_PARERR;
    if (Stat & STA_NOINIT)
        return RES_NOTRDY;

    offset = sector * 512;
    size = count * 512;
    return RES_OK;
}
#endif                          /* _READONLY */

/*-----------------------------------------------------------------------*/
/*
 * Miscellaneous Functions 
 */
/*-----------------------------------------------------------------------*/

#if _USE_IOCTL != 0
DRESULT disk_ioctl(BYTE drv,    /* Physical drive nmuber (0) */
                   BYTE ctrl,   /* Control code */
                   void *buff   /* Buffer to send/receive data block */
    )
{
    BYTE n, w, ofs, dl, dh, *ptr = (BYTE *) buff;


    if (drv)
        return RES_PARERR;
    if (Stat & STA_NOINIT)
        return RES_NOTRDY;

    switch (ctrl) {
        case GET_SECTOR_COUNT: /* Get number of sectors on the disk (DWORD) */
            ofs = 60;
            w = 2;
            n = 0;
            break;

        case GET_SECTOR_SIZE:  /* Get sectors on the disk (WORD) */
            *(WORD *) buff = 512;
            return RES_OK;

        case GET_BLOCK_SIZE:   /* Get erase block size in sectors (DWORD) */
            *(DWORD *) buff = 32;
            return RES_OK;

        default:
            return RES_PARERR;
    }
    return RES_OK;
}
#endif                          /* _USE_IOCTL != 0 */