RTOS/PROCESSOR-SDK-AM437X: FAT volume size issue

Part Number:PROCESSOR-SDK-AM437X

Tool/software:TI-RTOS

Hi,

I'm trying to make f_mkfs() work on TI-RTOS.
I define : 

#define	_USE_MKFS		1

in ffconf.h.

In example I add:

FATFS_DrvFxnTable FATFS_drvFxnTable = {
    MMCSD_close,
	CS_eMMC_control,//MMCSD_control
    MMCSD_init,
    MMCSD_open,
    MMCSD_write,
    MMCSD_read
};

In IOctr function, sector and block data reports was impelmented:

MMCSD_Error CS_eMMC_control(MMCSD_Handle handle, uint32_t cmd, void *arg){
//	MMCSD_OK
	MMCSD_v1_Object            *object = NULL;
	DWORD *tmp;
	tmp = arg;
    /* Input parameter validation */
    OSAL_Assert(handle == NULL);

    object = (MMCSD_v1_Object *)((MMCSD_Config *) handle)->object;

    switch(cmd){
    case CTRL_SYNC:
    	//check
    	return FATFS_OK;
    	break;
    case GET_SECTOR_COUNT:
    		*tmp = (DWORD)object->size / (DWORD)object->blockSize;
    	return FATFS_OK;
    	break;
    case GET_SECTOR_SIZE:
    	*tmp = (DWORD)object->blockSize;
    	return FATFS_OK;
    	break;
    case GET_BLOCK_SIZE:
    	*tmp = (DWORD)object->blockSize;
    	return FATFS_OK;
    	break;
    case CTRL_TRIM:
    	return FATFS_OK;
    	break;
    case CTRL_EJECT:
    	return MMCSD_close(handle);
    	break;
    default:
    	break;
    }
    return (((MMCSD_Config *) handle)->fxnTablePtr->controlFxn(handle, cmd, arg));
}

f_mkfs() make partition of approx. size  1.7MB or it fail to make filesiystem....

Any knowing issues?

Best Regards,

Mare