fatutil.h

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/*----------------------------------------------------------------------------
* Name:    fatutil.h
* Purpose: FAT utilities
* Version: V1.00
**----------------------------------------------------------------------------
*      This software is supplied "AS IS" without any warranties, express,
*      implied or statutory, including but not limited to the implied
*      warranties of fitness for purpose, satisfactory quality and
*      noninfringement. NXP extends you a royalty-free right to reproduce
*      and distribute executable files created using this software for use
*      on NXP Semiconductors LPC microcontroller devices only. Nothing else
*      gives you the right to use this software.
*
* Copyright (c) 2011 NXP Semiconductors. All rights reserved.
*---------------------------------------------------------------------------*/

#ifndef __FATUTIL_H__
#define __FATUTIL_H__

#include "usb.h"
#include "DataRam.h"
#define FAT12 1
#define FAT16 2
#define FAT32 3

#define UDIV_ROUNDUP(a, b) ((a + b - 1) / b)
#define FATTYPE FAT12

// #define DISKSIZE (VIRTUAL_MEMORY_BYTES)
#define DISKSIZE    (0x100000)
#define BYTESPERSECTOR (512)
#define RESERVEDSECTORCNT (1)
#define ROOTENTRIES (UDIV_ROUNDUP(BYTESPERSECTOR, 32))
// #define DIRECTORYSECTORCNT ((ROOTENTRIES - 1) / 16 + 1)
#define DIRECTORYSECTORCNT (UDIV_ROUNDUP(ROOTENTRIES, 16))
#define NUMFATS (2)
#define SECTORSPERCLUSTER (1)
#define DATASECTORS (1024)
// #define TOTALSECTORS  (NONDATASECTORS + 330)
#define TOTALSECTORS  (UDIV_ROUNDUP(DISKSIZE, BYTESPERSECTOR))
#define FATENTRIESPERSECTOR (UDIV_ROUNDUP(BYTESPERSECTOR * 8, 12 /*FAT12*/))
#define SECTORSPERFAT (UDIV_ROUNDUP(UDIV_ROUNDUP((TOTALSECTORS - RESERVEDSECTORCNT), SECTORSPERCLUSTER), \
         FATENTRIESPERSECTOR))

#define NONDATASECTORS (RESERVEDSECTORCNT + NUMFATS * SECTORSPERFAT + DIRECTORYSECTORCNT)
#define STARTDATAREGION (NONDATASECTORS * BYTESPERSECTOR)
#define BYTESPERCLUSTER (BYTESPERSECTOR * SECTORSPERCLUSTER)
#define FAT_MEDIA   (0xF0)

// Time of date of FIRMWARE.BIN on the USB Stick
#define TIME_HOUR   16
#define TIME_MIN    00
#define TIME_SEC    00
#define DATE_YEAR   2011 - 1980
#define DATE_MONTH  8
#define DATE_DAY    11

extern int32_t RootEntries;
extern int32_t BytesPerSector;
extern int32_t NumFats;
extern int32_t SectorsPerFat;
extern int32_t NonDataSectors;
extern int32_t TotalSectors;
extern int32_t StartDataRegion;

typedef struct {
 uint8_t     BS_jmpBoot[3]; /* Jump instruction to the boot code */
 uint8_t     BS_OEMName[8]; /* Name of system that formatted the volume */
 uint16_t    BPB_BytsPerSec; /* Bytes per sector (should be 512) */
 uint8_t     BPB_SecPerClus; /* Sectors per cluster (FAT-12 = 1) */
 uint16_t    BPB_RsvdSecCnt; /* Reserved sectors (FAT-12 = 1) */
 uint8_t     BPB_NumFATs; /* FAT tables on the disk (should be 2) */
 uint16_t    BPB_RootEntCnt; /* Max directory entries in root directory */
 uint16_t    BPB_TotSec16; /* Total number of sectors on the disk (FAT-12 and FAT-16) */
 uint8_t     BPB_Media;  /* Media type {fixed, removable, etc.} */
 uint16_t    BPB_FATSz16; /* Sector size of FAT table (FAT-12 = 9) */
 uint16_t    BPB_SecPerTrk; /* # of sectors per cylindrical track */
 uint16_t    BPB_NumHeads; /* # of heads per volume (1.4Mb 3.5" = 2) */
 uint32_t    BPB_HiddSec; /* # of preceding hidden sectors (0) */
 uint32_t    BPB_TotSec32; /* # of FAT-32 sectors (0 for FAT-12) */
 uint8_t     BS_DrvNum;  /* A drive number for the media (OS specific) */
 uint8_t     BS_Reserved1; /* Reserved space for Windows NT (set to 0) */
 uint8_t     BS_BootSig;  /* (0x29) Indicates following: */
 uint32_t    BS_VolID;  /* Volume serial # (for tracking this disk) */
 uint8_t     BS_VolLab[11]; /* Volume label (RDL or "NO NAME    ") */
 uint8_t     BS_FilSysType[8]; /* Deceptive FAT type Label */
} ATTR_PACKED BSStruct;

typedef struct {
 uint8_t FATByte[BYTESPERSECTOR * SECTORSPERFAT];
} ATTR_PACKED FAT;

typedef struct {    // (total 16 bits--a unsigned short)
 uint16_t sec : 5; // low-order 5 bits are the seconds
 uint16_t min : 6; // next 6 bits are the minutes
 uint16_t hour : 5; // high-order 5 bits are the hour
} ATTR_PACKED FATTime;

typedef struct {    // (total 16 bits--a unsigned short)
 uint16_t day : 5; // low-order 5 bits are the day
 uint16_t month : 4; // next 4 bits are the month
 uint16_t year : 7; // high-order 7 bits are the year
} ATTR_PACKED FATDate;

typedef struct {
 uint8_t     Name[8];  /* File name (capital letters, padded w/spaces) */
 uint8_t     Extension[3]; /* Extension (same format as name, no '.') */
 uint8_t     Attributes;  /* Holds the attributes code */
 uint8_t     Reserved[10]; /* Reserved for Windows NT (Set to zero!) */
 FATTime     Time;   /* Time of last write */
 FATDate     Date;   /* Date of last write */
 uint16_t    startCluster; /* Pointer to the first cluster of the file */
 uint32_t    fileSize;  /* File size in bytes */
} ATTR_PACKED DirEntry;

typedef struct _diskimage {
 BSStruct BootSector;
 uint8_t BootCode[448];
 uint16_t BootSectorSignature;
 FAT Fat[NUMFATS];
 DirEntry DirectoryEntries[ROOTENTRIES];
} DISKIMAGE;

int16_t GetFAT12Entry(DISKIMAGE *DiskImagePtr, int FATindex);

void SetFAT12Entry(DISKIMAGE *DiskImagePtr, int FATindex, unsigned short FAT12ClusEntryVal);

uint32_t CalculateCountOfClusters(DISKIMAGE *DiskImagePtr);

void CreateDiskImage(DISKIMAGE *DiskImagePtr);

void SetDiskMetricsFromDiskImage(DISKIMAGE *DiskImagePtr);

void InitializeDiskDiskImage(DISKIMAGE *DiskImagePtr);

void InitializeFAT12(DISKIMAGE *DiskImagePtr);

#endif  /* __FATUTIL_H__ */