DOLDVDFormat

From Rare Gaming Dump

GameCube Disc Format aka NROM(Read-only) or NR-Disc(Rewritable), based on DVD tech.

Please Note this is a work in progress doc.

DVD Sector Scrambling(XOR) is done using Disk ID(gamecode + makercode), it is 6 bytes and of 16 Random Numbers to pick from to scramble the DVD sectors, done by the Disc Drive Firmware, it is stored on a on-chip ROM, however for the MN102 Firmware it is stored on a on-board ROM chip that stores the firmware it is 128KB

Panasonic MN103S (32 bit) is the Disk Controller(ECC, Servo Control, Descramble, XADPCM Decoding)
Panasonic MN102H (16 bit) is the System Controller(Manager, Checks Copy protection, Handles Commands, Checks Disc Type, Etc.)

The development tools used to develop for these Panasonic microcontrollers is called Debug Factory 3, it comes with a toolchain that has compiler, linker, assembler.

Panasonic Debug Factory 3 MN102
In the firmware the text "Nintendo Game Disk" can be found this is the Media ID 19 byte string that is used as meta data in the lead-in area of the DVD.
MN102H looks for this string to check if the disc type is a GameCube\Wii Game Disc.
It's also does the BCA copy protection check.

Data Types

  u8 = unsigned char (1 byte) or string
  s8 = signed char (1 byte) or string
  u16 = unsigned short (2 bytes)
  s16 = signed short (2 bytes)
  u32 = unsigned int (4 bytes)
  s32 = signed int (4 bytes)
  u64 = unsigned long long (8 bytes)
  s64 = signed long long (8 bytes)

Data Frame

   u32 id; // PSN(Physical Sector Number)
   u16 ied; // ID Error Detection Code, CRC16
   u8 userdata[2048]; // Sector Data
   u8 cpr_mai[6]; // Copyright Management Information(Not used)
   u32 edc; // Error Detection Code, CRC32
   // 2064B

Random Numbers

   0: 3
   1: 48
   2: 32512
   3: 28673
   4: 6
   5: 69
   6: 32256
   7: 24579
   8: 12
   9: 192
   10: 31744
   11: 16391
   12: 24
   13: 384
   14: 30720
   15: 15

DiscId

   char gamecode[4];
   char makercode[2];
   u8 diskNumber;
   u8 version;
   u8 streaming;
   u8 streamingBufferSize;
   u8 pad[18];
   u32 magic;

Burst Cutting Area

   // UserData(unencrypted), 64B
   u8 optionalInfo[52];
   u8 manufacturer[2];
   u8 recorderDevice[2];
   u8 bcaSerial;
   u8 discDate[2];
   u8 discTime[2];
   u8 discNumber[3];
   // SecureData(unencrypted), 12B
   u8 key[8]; // used to xor scramble the 6 sector locations data
   u8 id[4];
   // AuthenticationData(encrypted), 48B
   PsnRegion psn[6]; // 6 sector locations
   // 188 Total Bytes
   
   struct_PsnRegion
   {
       u32 start;
       u32 end;
   };

Disc Physical Format

   // Leadin Area
   PhysicalFormatInfo pfi;
   DiscManufacturingInfo dmi;

PhysicalFormatInfo

   u8 reserved[6];
   u8 discMagic; // value is -1.
   u8 discSizeMinTransferRate; // The value is fixed on 16.
   u8 discStructure; // The value is fixed on 1.
   u8 recordedDensity; // The value is fixed on 1.
   DataAreaAllocation m_dataAreaAllocation;
   u8 reversed2[2026];
   u8 reversed3[6];

DiscManufacturingInfo

   u8 reversed[6];
   u8 unknown1[6];
   u8 randomNumber2[6];
   u8 unknown2[6];
   u8 randomNumber3[6];
   char mediaId[19]; // "Nintendo Game Disk"
   u8 randomNumber4[6];
   u8 bookTypePartVersion; // value must be 1.
   u8 discSizeMinReadoutRate; // The value is fixed on 16.
   u8 discStructure; // The value is fixed on 1.
   u8 recordedDensity; // The value is fixed on 0.
   DataAreaAllocation dataAreaAllocation;
   u8 bcaDescriptor; // The value is fixed on 128.
   u8 reserved2[1983];
   u8 reserved3[6];

DataAreaAllocation

   u8 reserved;
   u16 startSector;
   u8 reserved2;
   u16 endSector;
   u8 reserved3[3];
   // 12 Bytes

Disc Image Format

   BootHeader m_header;
   BootHeaderInfo m_bi;
   AppLoader m_apploader;
   FileSystemTable m_fst;
   u8* userdata; // application is stored here, including boot file

BootHeader

   u8 game_code[4];
   u8 company_code[2];
   u8 diskNumber;
   u8 gameVersion;
   u8 audioStreaming;
   u8 streamBufSize;
   u8 unused_1[18];    
   u32 magic; // 3258163005
   char gameName[64];
   u8 unused_2[416];
   u32 nkitMagicWord;
   u32 nkitVersion;
   u32 dataCRC;
   u32 headerCRC;
   u32 dataSize;
   u32 junkId;
   u8 unused_3[488];
   u32 apploaderSize;
   u32 apploaderInit;
   u32 apploaderMain;
   u32 apploaderExit;
   u8 unused_4[16];
   u32 bootOffset;
   u32 fstOffset;
   u32 fstSize;
   u32 maxFstSize;
   u32 fstAddress;
   u32 userPos;
   u32 userLength;
   u32 unused_5;

BootHeaderInfo

   u32 debugMonSize; // debug monitor size
   u32 simMemSize; // size of simulator memory
   u32 argOffset;
   u32 debugFlag;
   u32 debugOffset;
   u32 debugSize;
   u32 country;
   u32 totalDisc;
   u32 supportLongFileName;
   u32 padSpec;
   u32 dolLimit;
   u8 unused_6[8148];
   // 8192 Bytes

AppLoader

   char date[16];
   u32 entryAddress;
   u32 size;
   u32 rebootSize;
   u8 pad[4];
   u8* code;

FileSystemTable

   u32 entryCount;
   FileSystemEntity* m_entity;
   StringTable* m_string;

FileSystemEntity

   u8 flags;
   u16 filenameOffset;
   u32 fileOffset;
   u32 fileSize;

StringTable

   char* name;
   u8 pad;