melonDS/NDSCart.cpp
StapleButter 971e7b7e89 well, GX FIFO base. noting that for now, it doesn't do much beyond getting full real quick.
also make ROM loading fail gracefully if it shits itself, instead of entering an endless loop.
2017-02-07 23:31:21 +01:00

940 lines
20 KiB
C++

/*
Copyright 2016-2017 StapleButter
This file is part of melonDS.
melonDS is free software: you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation, either version 3 of the License, or (at your option)
any later version.
melonDS is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with melonDS. If not, see http://www.gnu.org/licenses/.
*/
#include <stdio.h>
#include <string.h>
#include "NDS.h"
#include "NDSCart.h"
namespace NDSCart_SRAM
{
u8* SRAM;
u32 SRAMLength;
char SRAMPath[256];
void (*WriteFunc)(u8 val, bool islast);
u32 Discover_MemoryType;
u32 Discover_Likeliness;
u8* Discover_Buffer;
u32 Discover_DataPos;
u32 Hold;
u8 CurCmd;
u32 DataPos;
u8 Data;
u8 StatusReg;
u32 Addr;
void Write_Null(u8 val, bool islast);
void Write_EEPROMTiny(u8 val, bool islast);
void Write_EEPROM(u8 val, bool islast);
void Write_Flash(u8 val, bool islast);
void Write_Discover(u8 val, bool islast);
bool Init()
{
SRAM = NULL;
Discover_Buffer = NULL;
return true;
}
void DeInit()
{
if (SRAM) delete[] SRAM;
if (Discover_Buffer) delete[] Discover_Buffer;
}
void Reset()
{
}
void LoadSave(char* path)
{
if (SRAM) delete[] SRAM;
if (Discover_Buffer) delete[] Discover_Buffer;
Discover_Buffer = NULL;
strncpy(SRAMPath, path, 255);
SRAMPath[255] = '\0';
FILE* f = fopen(path, "rb");
if (f)
{
fseek(f, 0, SEEK_END);
SRAMLength = (u32)ftell(f);
SRAM = new u8[SRAMLength];
fseek(f, 0, SEEK_SET);
fread(SRAM, SRAMLength, 1, f);
fclose(f);
switch (SRAMLength)
{
case 512: WriteFunc = Write_EEPROMTiny; break;
case 8192:
case 65536: WriteFunc = Write_EEPROM; break;
case 256*1024:
case 512*1024:
case 1024*1024:
case 8192*1024: WriteFunc = Write_Flash; break;
default:
printf("!! BAD SAVE LENGTH %d\n", SRAMLength);
WriteFunc = Write_Null;
break;
}
}
else
{
SRAMLength = 0;
WriteFunc = Write_Discover;
Discover_MemoryType = 2;
Discover_Likeliness = 0;
Discover_DataPos = 0;
Discover_Buffer = new u8[256*1024];
memset(Discover_Buffer, 0, 256*1024);
}
Hold = 0;
CurCmd = 0;
Data = 0;
StatusReg = 0x00;
}
u8 Read()
{
return Data;
}
void SetMemoryType()
{
switch (Discover_MemoryType)
{
case 1:
printf("Save memory type: EEPROM 4k\n");
WriteFunc = Write_EEPROMTiny;
SRAMLength = 512;
break;
case 2:
printf("Save memory type: EEPROM 64k\n");
WriteFunc = Write_EEPROM;
SRAMLength = 8192;
break;
case 3:
printf("Save memory type: EEPROM 512k\n");
WriteFunc = Write_EEPROM;
SRAMLength = 65536;
break;
case 4:
printf("Save memory type: Flash. Hope the size is 256K.\n");
WriteFunc = Write_Flash;
SRAMLength = 256*1024;
break;
case 5:
printf("Save memory type: ...something else\n");
WriteFunc = Write_Null;
SRAMLength = 0;
break;
}
if (!SRAMLength)
return;
SRAM = new u8[SRAMLength];
// replay writes that occured during discovery
u8 prev_cmd = CurCmd;
u32 pos = 0;
while (pos < 256*1024)
{
u32 len = *(u32*)&Discover_Buffer[pos];
pos += 4;
if (len == 0) break;
CurCmd = Discover_Buffer[pos++];
DataPos = 0;
Addr = 0;
Data = 0;
for (u32 i = 1; i < len; i++)
{
WriteFunc(Discover_Buffer[pos++], (i==(len-1)));
DataPos++;
}
}
CurCmd = prev_cmd;
delete[] Discover_Buffer;
}
void Write_Discover(u8 val, bool islast)
{
// attempt at autodetecting the type of save memory.
// we basically hope the game will be nice and clear whole pages of memory.
if (CurCmd == 0x03 || CurCmd == 0x0B)
{
if (Discover_Likeliness)
{
// apply. and pray.
SetMemoryType();
DataPos = 0;
Addr = 0;
Data = 0;
return WriteFunc(val, islast);
}
else
{
Data = 0;
return;
}
}
if (CurCmd == 0x02 || CurCmd == 0x0A)
{
if (DataPos == 0)
Discover_Buffer[Discover_DataPos + 4] = CurCmd;
Discover_Buffer[Discover_DataPos + 5 + DataPos] = val;
if (islast)
{
u32 len = DataPos+1;
*(u32*)&Discover_Buffer[Discover_DataPos] = len+1;
Discover_DataPos += 5+len;
if (Discover_Likeliness <= len)
{
Discover_Likeliness = len;
if (len > 3+256) // bigger Flash, FRAM, whatever
{
Discover_MemoryType = 5;
}
else if (len > 2+128) // Flash
{
Discover_MemoryType = 4;
}
else if (len > 2+32) // EEPROM 512k
{
Discover_MemoryType = 3;
}
else if (len > 1+16 || (len != 1+16 && CurCmd != 0x0A)) // EEPROM 64k
{
Discover_MemoryType = 2;
}
else // EEPROM 4k
{
Discover_MemoryType = 1;
}
}
printf("discover: type=%d likeliness=%d\n", Discover_MemoryType, Discover_Likeliness);
}
}
}
void Write_Null(u8 val, bool islast) {}
void Write_EEPROMTiny(u8 val, bool islast)
{
// TODO
}
void Write_EEPROM(u8 val, bool islast)
{
switch (CurCmd)
{
case 0x02:
if (DataPos < 2)
{
Addr <<= 8;
Addr |= val;
Data = 0;
}
else
{
SRAM[Addr & (SRAMLength-1)] = val;
Addr++;
}
break;
case 0x03:
if (DataPos < 2)
{
Addr <<= 8;
Addr |= val;
Data = 0;
}
else
{
Data = SRAM[Addr & (SRAMLength-1)];
Addr++;
}
break;
case 0x9F:
Data = 0xFF;
break;
default:
if (DataPos==0)
printf("unknown EEPROM save command %02X\n", CurCmd);
break;
}
}
void Write_Flash(u8 val, bool islast)
{
switch (CurCmd)
{
case 0x03:
if (DataPos < 3)
{
Addr <<= 8;
Addr |= val;
Data = 0;
}
else
{
// CHECKME: does Flash also wraparound when the address is out of bounds?
if (Addr >= SRAMLength)
Data = 0;
else
Data = SRAM[Addr];
Addr++;
}
break;
case 0x0A:
if (DataPos < 3)
{
Addr <<= 8;
Addr |= val;
Data = 0;
}
else
{
if (Addr < SRAMLength)
SRAM[Addr] = val;
Addr++;
}
break;
case 0x9F:
Data = 0xFF;
break;
default:
if (DataPos==0)
printf("unknown Flash save command %02X\n", CurCmd);
break;
}
}
void Write(u8 val, u32 hold)
{
bool islast = false;
if (!hold)
{
if (Hold) islast = true;
Hold = 0;
}
if (hold && (!Hold))
{
CurCmd = val;
Hold = 1;
Data = 0;
DataPos = 0;
Addr = 0;
//printf("save SPI command %02X\n", CurCmd);
return;
}
switch (CurCmd)
{
case 0x02:
case 0x03:
case 0x0A:
case 0x0B:
case 0x9F:
WriteFunc(val, islast);
DataPos++;
break;
case 0x04: // write disable
StatusReg &= ~(1<<1);
Data = 0;
break;
case 0x05: // read status reg
Data = StatusReg;
break;
case 0x06: // write enable
StatusReg |= (1<<1);
Data = 0;
break;
default:
if (DataPos==0)
printf("unknown save SPI command %02X\n", CurCmd);
break;
}
if (islast && (CurCmd == 0x02 || CurCmd == 0x0A))
{
FILE* f = fopen(SRAMPath, "wb");
if (f)
{
fwrite(SRAM, SRAMLength, 1, f);
fclose(f);
}
}
}
}
namespace NDSCart
{
u16 SPICnt;
u32 ROMCnt;
u8 ROMCommand[8];
u32 ROMDataOut;
u8 DataOut[0x4000];
u32 DataOutPos;
u32 DataOutLen;
bool CartInserted;
u8* CartROM;
u32 CartROMSize;
u32 CartID;
bool CartIsHomebrew;
u32 CmdEncMode;
u32 DataEncMode;
u32 Key1_KeyBuf[0x412];
u64 Key2_X;
u64 Key2_Y;
u32 ByteSwap(u32 val)
{
return (val >> 24) | ((val >> 8) & 0xFF00) | ((val << 8) & 0xFF0000) | (val << 24);
}
void Key1_Encrypt(u32* data)
{
u32 y = data[0];
u32 x = data[1];
u32 z;
for (u32 i = 0x0; i <= 0xF; i++)
{
z = Key1_KeyBuf[i] ^ x;
x = Key1_KeyBuf[0x012 + (z >> 24) ];
x += Key1_KeyBuf[0x112 + ((z >> 16) & 0xFF)];
x ^= Key1_KeyBuf[0x212 + ((z >> 8) & 0xFF)];
x += Key1_KeyBuf[0x312 + (z & 0xFF)];
x ^= y;
y = z;
}
data[0] = x ^ Key1_KeyBuf[0x10];
data[1] = y ^ Key1_KeyBuf[0x11];
}
void Key1_Decrypt(u32* data)
{
u32 y = data[0];
u32 x = data[1];
u32 z;
for (u32 i = 0x11; i >= 0x2; i--)
{
z = Key1_KeyBuf[i] ^ x;
x = Key1_KeyBuf[0x012 + (z >> 24) ];
x += Key1_KeyBuf[0x112 + ((z >> 16) & 0xFF)];
x ^= Key1_KeyBuf[0x212 + ((z >> 8) & 0xFF)];
x += Key1_KeyBuf[0x312 + (z & 0xFF)];
x ^= y;
y = z;
}
data[0] = x ^ Key1_KeyBuf[0x1];
data[1] = y ^ Key1_KeyBuf[0x0];
}
void Key1_ApplyKeycode(u32* keycode, u32 mod)
{
Key1_Encrypt(&keycode[1]);
Key1_Encrypt(&keycode[0]);
u32 temp[2] = {0,0};
for (u32 i = 0; i <= 0x11; i++)
{
Key1_KeyBuf[i] ^= ByteSwap(keycode[i % mod]);
}
for (u32 i = 0; i <= 0x410; i+=2)
{
Key1_Encrypt(temp);
Key1_KeyBuf[i ] = temp[1];
Key1_KeyBuf[i+1] = temp[0];
}
}
void Key1_InitKeycode(u32 idcode, u32 level, u32 mod)
{
memcpy(Key1_KeyBuf, &NDS::ARM7BIOS[0x30], 0x1048); // hax
u32 keycode[3] = {idcode, idcode>>1, idcode<<1};
if (level >= 1) Key1_ApplyKeycode(keycode, mod);
if (level >= 2) Key1_ApplyKeycode(keycode, mod);
if (level >= 3)
{
keycode[1] <<= 1;
keycode[2] >>= 1;
Key1_ApplyKeycode(keycode, mod);
}
}
void Key2_Encrypt(u8* data, u32 len)
{
for (u32 i = 0; i < len; i++)
{
Key2_X = (((Key2_X >> 5) ^
(Key2_X >> 17) ^
(Key2_X >> 18) ^
(Key2_X >> 31)) & 0xFF)
+ (Key2_X << 8);
Key2_Y = (((Key2_Y >> 5) ^
(Key2_Y >> 23) ^
(Key2_Y >> 18) ^
(Key2_Y >> 31)) & 0xFF)
+ (Key2_Y << 8);
Key2_X &= 0x0000007FFFFFFFFFULL;
Key2_Y &= 0x0000007FFFFFFFFFULL;
}
}
bool Init()
{
if (!NDSCart_SRAM::Init()) return false;
return true;
}
void DeInit()
{
NDSCart_SRAM::DeInit();
}
void Reset()
{
SPICnt = 0;
ROMCnt = 0;
memset(ROMCommand, 0, 8);
ROMDataOut = 0;
Key2_X = 0;
Key2_Y = 0;
memset(DataOut, 0, 0x4000);
DataOutPos = 0;
DataOutLen = 0;
CartInserted = false;
CartROM = NULL;
CartROMSize = 0;
CartID = 0;
CartIsHomebrew = false;
CmdEncMode = 0;
DataEncMode = 0;
NDSCart_SRAM::Reset();
}
bool LoadROM(char* path)
{
// TODO: streaming mode? for really big ROMs or systems with limited RAM
// for now we're lazy
FILE* f = fopen(path, "rb");
if (!f)
{
printf("Failed to open ROM file %s\n", path);
return false;
}
fseek(f, 0, SEEK_END);
u32 len = (u32)ftell(f);
CartROMSize = 0x200;
while (CartROMSize < len)
CartROMSize <<= 1;
u32 gamecode;
fseek(f, 0x0C, SEEK_SET);
fread(&gamecode, 4, 1, f);
CartROM = new u8[CartROMSize];
memset(CartROM, 0, CartROMSize);
fseek(f, 0, SEEK_SET);
fread(CartROM, 1, len, f);
fclose(f);
//CartROM = f;
// temp. TODO: later make this user selectable
// calling this sets up shit for booting from the cart directly.
// normal behavior is booting from the BIOS.
NDS::SetupDirectBoot();
CartInserted = true;
// generate a ROM ID
// note: most games don't check the actual value
// it just has to stay the same throughout gameplay
CartID = 0x00001FC2;
u32 arm9base = *(u32*)&CartROM[0x20];
if (arm9base < 0x8000)
{
if (arm9base >= 0x4000)
{
// reencrypt secure area if needed
if (*(u32*)&CartROM[arm9base] == 0xE7FFDEFF)
{
printf("Re-encrypting cart secure area\n");
strncpy((char*)&CartROM[arm9base], "encryObj", 8);
Key1_InitKeycode(gamecode, 3, 2);
for (u32 i = 0; i < 0x800; i += 8)
Key1_Encrypt((u32*)&CartROM[arm9base + i]);
Key1_InitKeycode(gamecode, 2, 2);
Key1_Encrypt((u32*)&CartROM[arm9base]);
}
}
else
CartIsHomebrew = true;
}
// encryption
Key1_InitKeycode(gamecode, 2, 2);
// save
char savepath[256];
strncpy(savepath, path, 255);
savepath[255] = '\0';
strncpy(savepath + strlen(path) - 3, "sav", 3);
printf("Save file: %s\n", savepath);
NDSCart_SRAM::LoadSave(savepath);
return true;
}
void ReadROM(u32 addr, u32 len, u32 offset)
{
if (!CartInserted) return;
if (addr >= CartROMSize) return;
if ((addr+len) > CartROMSize)
len = CartROMSize - addr;
memcpy(DataOut+offset, CartROM+addr, len);
}
void ReadROM_B7(u32 addr, u32 len, u32 offset)
{
addr &= (CartROMSize-1);
if (!CartIsHomebrew)
{
if (addr < 0x8000)
addr = 0x8000 + (addr & 0x1FF);
}
memcpy(DataOut+offset, CartROM+addr, len);
}
void EndTransfer()
{
ROMCnt &= ~(1<<23);
ROMCnt &= ~(1<<31);
if (SPICnt & (1<<14))
NDS::TriggerIRQ((NDS::ExMemCnt[0]>>11)&0x1, NDS::IRQ_CartSendDone);
}
void ROMPrepareData(u32 param)
{
if (DataOutPos >= DataOutLen)
ROMDataOut = 0;
else
ROMDataOut = *(u32*)&DataOut[DataOutPos];
DataOutPos += 4;
ROMCnt |= (1<<23);
NDS::CheckDMAs(0, 0x06);
NDS::CheckDMAs(1, 0x12);
//if (DataOutPos < DataOutLen)
// NDS::ScheduleEvent((ROMCnt & (1<<27)) ? 8:5, ROMPrepareData, 0);
}
void WriteROMCnt(u32 val)
{
ROMCnt = val & 0xFF7F7FFF;
if (!(SPICnt & (1<<15))) return;
if (val & (1<<15))
{
u32 snum = (NDS::ExMemCnt[0]>>8)&0x8;
u64 seed0 = *(u32*)&NDS::ROMSeed0[snum] | ((u64)NDS::ROMSeed0[snum+4] << 32);
u64 seed1 = *(u32*)&NDS::ROMSeed1[snum] | ((u64)NDS::ROMSeed1[snum+4] << 32);
Key2_X = 0;
Key2_Y = 0;
for (u32 i = 0; i < 39; i++)
{
if (seed0 & (1ULL << i)) Key2_X |= (1ULL << (38-i));
if (seed1 & (1ULL << i)) Key2_Y |= (1ULL << (38-i));
}
printf("seed0: %02X%08X\n", (u32)(seed0>>32), (u32)seed0);
printf("seed1: %02X%08X\n", (u32)(seed1>>32), (u32)seed1);
printf("key2 X: %02X%08X\n", (u32)(Key2_X>>32), (u32)Key2_X);
printf("key2 Y: %02X%08X\n", (u32)(Key2_Y>>32), (u32)Key2_Y);
}
if (!(ROMCnt & (1<<31))) return;
u32 datasize = (ROMCnt >> 24) & 0x7;
if (datasize == 7)
datasize = 4;
else if (datasize > 0)
datasize = 0x100 << datasize;
DataOutPos = 0;
DataOutLen = datasize;
// handle KEY1 encryption as needed.
// KEY2 encryption is implemented in hardware and doesn't need to be handled.
u8 cmd[8];
if (CmdEncMode == 1)
{
*(u32*)&cmd[0] = ByteSwap(*(u32*)&ROMCommand[4]);
*(u32*)&cmd[4] = ByteSwap(*(u32*)&ROMCommand[0]);
Key1_Decrypt((u32*)cmd);
u32 tmp = ByteSwap(*(u32*)&cmd[4]);
*(u32*)&cmd[4] = ByteSwap(*(u32*)&cmd[0]);
*(u32*)&cmd[0] = tmp;
}
else
{
*(u32*)&cmd[0] = *(u32*)&ROMCommand[0];
*(u32*)&cmd[4] = *(u32*)&ROMCommand[4];
}
/*printf("ROM COMMAND %04X %08X %02X%02X%02X%02X%02X%02X%02X%02X SIZE %04X\n",
SPICnt, ROMCnt,
cmd[0], cmd[1], cmd[2], cmd[3],
cmd[4], cmd[5], cmd[6], cmd[7],
datasize);*/
switch (cmd[0])
{
case 0x9F:
memset(DataOut, 0xFF, DataOutLen);
break;
case 0x00:
memset(DataOut, 0, DataOutLen);
if (DataOutLen > 0x1000)
{
ReadROM(0, 0x1000, 0);
for (u32 pos = 0x1000; pos < DataOutLen; pos += 0x1000)
memcpy(DataOut+pos, DataOut, 0x1000);
}
else
ReadROM(0, DataOutLen, 0);
break;
case 0x90:
case 0xB8:
for (u32 pos = 0; pos < DataOutLen; pos += 4)
*(u32*)&DataOut[pos] = CartID;
break;
case 0x3C:
CmdEncMode = 1;
break;
case 0xB7:
{
u32 addr = (cmd[1]<<24) | (cmd[2]<<16) | (cmd[3]<<8) | cmd[4];
memset(DataOut, 0, DataOutLen);
if (((addr + DataOutLen - 1) >> 12) != (addr >> 12))
{
u32 len1 = 0x1000 - (addr & 0xFFF);
ReadROM_B7(addr, len1, 0);
ReadROM_B7(addr+len1, DataOutLen-len1, len1);
}
else
ReadROM_B7(addr, DataOutLen, 0);
}
break;
default:
switch (cmd[0] & 0xF0)
{
case 0x40:
DataEncMode = 2;
break;
case 0x10:
for (u32 pos = 0; pos < DataOutLen; pos += 4)
*(u32*)&DataOut[pos] = CartID;
break;
case 0x20:
{
u32 addr = (cmd[2] & 0xF0) << 8;
ReadROM(addr, 0x1000, 0);
}
break;
case 0xA0:
CmdEncMode = 2;
break;
}
break;
}
//ROMCnt &= ~(1<<23);
ROMCnt |= (1<<23);
if (datasize == 0)
EndTransfer();
else
{
NDS::CheckDMAs(0, 0x05);
NDS::CheckDMAs(1, 0x12);
}
//NDS::ScheduleEvent((ROMCnt & (1<<27)) ? 8:5, ROMPrepareData, 0);
}
u32 ReadROMData()
{
/*if (ROMCnt & (1<<23))
{
ROMCnt &= ~(1<<23);
if (DataOutPos >= DataOutLen)
EndTransfer();
}
return ROMDataOut;*/
u32 ret;
if (DataOutPos >= DataOutLen)
ret = 0;
else
ret = *(u32*)&DataOut[DataOutPos];
DataOutPos += 4;
if (DataOutPos == DataOutLen)
EndTransfer();
return ret;
}
void DMA(u32 addr)
{
void (*writefn)(u32,u32) = (NDS::ExMemCnt[0] & (1<<11)) ? NDS::ARM7Write32 : NDS::ARM9Write32;
for (u32 i = 0; i < DataOutLen; i+=4)
{
writefn(addr+i, *(u32*)&DataOut[i]);
}
EndTransfer();
}
void WriteSPICnt(u16 val)
{
SPICnt = (SPICnt & 0x0080) | (val & 0xE043);
}
u8 ReadSPIData()
{
if (!(SPICnt & (1<<15))) return 0;
if (!(SPICnt & (1<<13))) return 0;
return NDSCart_SRAM::Read();
}
void WriteSPIData(u8 val)
{
if (!(SPICnt & (1<<15))) return;
if (!(SPICnt & (1<<13))) return;
// TODO: take delays into account
NDSCart_SRAM::Write(val, SPICnt&(1<<6));
}
}