src/Flash.c

   1 // VisualBoyAdvance - Nintendo Gameboy/GameboyAdvance (TM) emulator.
   2 // Copyright (C) 1999-2003 Forgotten
   3 // Copyright (C) 2004-2006 Forgotten and the VBA development team
   4
   5 // This program is free software; you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation; either version 2, or(at your option)
   8 // any later version.
   9 //
  10 // This program is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with this program; if not, write to the Free Software Foundation,
  17 // Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18
  19 #include <stdio.h>
  20 #include <memory.h>
  21 #include "GBA.h"
  22 #include "Globals.h"
  23 #include "Flash.h"
  24 #include "Sram.h"
  25 #include "Util.h"
  26
  27 #define FLASH_READ_ARRAY         0
  28 #define FLASH_CMD_1              1
  29 #define FLASH_CMD_2              2
  30 #define FLASH_AUTOSELECT         3
  31 #define FLASH_CMD_3              4
  32 #define FLASH_CMD_4              5
  33 #define FLASH_CMD_5              6
  34 #define FLASH_ERASE_COMPLETE     7
  35 #define FLASH_PROGRAM            8
  36 #define FLASH_SETBANK            9
  37
  38 u8 flashSaveMemory[0x20000];
  39 int flashState = FLASH_READ_ARRAY;
  40 int flashReadState = FLASH_READ_ARRAY;
  41 int flashSize = 0x10000;
  42 int flashDeviceID = 0x1b;
  43 int flashManufacturerID = 0x32;
  44 int flashBank = 0;
  45
  46 static variable_desc flashSaveData[] = {
  47   { &flashState, sizeof(int) },
  48   { &flashReadState, sizeof(int) },
  49   { &flashSaveMemory[0], 0x10000 },
  50   { NULL, 0 }
  51 };
  52
  53 static variable_desc flashSaveData2[] = {
  54   { &flashState, sizeof(int) },
  55   { &flashReadState, sizeof(int) },
  56   { &flashSize, sizeof(int) },
  57   { &flashSaveMemory[0], 0x20000 },
  58   { NULL, 0 }
  59 };
  60
  61 static variable_desc flashSaveData3[] = {
  62   { &flashState, sizeof(int) },
  63   { &flashReadState, sizeof(int) },
  64   { &flashSize, sizeof(int) },
  65   { &flashBank, sizeof(int) },
  66   { &flashSaveMemory[0], 0x20000 },
  67   { NULL, 0 }
  68 };
  69
  70 void flashInit()
  71 {
  72   memset(flashSaveMemory, 0xff, sizeof(flashSaveMemory));
  73 }
  74
  75 void flashReset()
  76 {
  77   flashState = FLASH_READ_ARRAY;
  78   flashReadState = FLASH_READ_ARRAY;
  79   flashBank = 0;
  80 }
  81
  82 void flashSaveGame(gzFile gzFile)
  83 {
  84   utilWriteData(gzFile, flashSaveData3);
  85 }
  86
  87 void flashReadGame(gzFile gzFile, int version)
  88 {
  89   if(version < SAVE_GAME_VERSION_5)
  90     utilReadData(gzFile, flashSaveData);
  91   else if(version < SAVE_GAME_VERSION_7) {
  92     utilReadData(gzFile, flashSaveData2);
  93     flashBank = 0;
  94     flashSetSize(flashSize);
  95   } else {
  96     utilReadData(gzFile, flashSaveData3);
  97   }
  98 }
  99
 100 void flashSetSize(int size)
 101 {
 102   //  log("Setting flash size to %d\n", size);
 103   if(size == 0x10000) {
 104     flashDeviceID = 0x1b;
 105     flashManufacturerID = 0x32;
 106   } else {
 107     flashDeviceID = 0x13; //0x09;
 108     flashManufacturerID = 0x62; //0xc2;
 109   }
 110   // Added to make 64k saves compatible with 128k ones
 111   // (allow wrongfuly set 64k saves to work for Pokemon games)
 112   if ((size == 0x20000) && (flashSize == 0x10000))
 113     memcpy((u8 *)(flashSaveMemory+0x10000), (u8 *)(flashSaveMemory), 0x10000);
 114   flashSize = size;
 115 }
 116
 117 u8 flashRead(u32 address)
 118 {
 119   //  log("Reading %08x from %08x\n", address, reg[15].I);
 120   //  log("Current read state is %d\n", flashReadState);
 121   address &= 0xFFFF;
 122
 123   switch(flashReadState) {
 124   case FLASH_READ_ARRAY:
 125     return flashSaveMemory[(flashBank << 16) + address];
 126   case FLASH_AUTOSELECT:
 127     switch(address & 0xFF) {
 128     case 0:
 129       // manufacturer ID
 130       return flashManufacturerID;
 131     case 1:
 132       // device ID
 133       return flashDeviceID;
 134     }
 135     break;
 136   case FLASH_ERASE_COMPLETE:
 137     flashState = FLASH_READ_ARRAY;
 138     flashReadState = FLASH_READ_ARRAY;
 139     return 0xFF;
 140   };
 141   return 0;
 142 }
 143
 144 void flashSaveDecide(u32 address, u8 byte)
 145 {
 146   //  log("Deciding save type %08x\n", address);
 147   if(address == 0x0e005555) {
 148     saveType = 2;
 149     cpuSaveGameFunc = flashWrite;
 150   } else {
 151     saveType = 1;
 152     cpuSaveGameFunc = sramWrite;
 153   }
 154
 155   (*cpuSaveGameFunc)(address, byte);
 156 }
 157
 158 void flashDelayedWrite(u32 address, u8 byte)
 159 {
 160   saveType = 2;
 161   cpuSaveGameFunc = flashWrite;
 162   flashWrite(address, byte);
 163 }
 164
 165 void flashWrite(u32 address, u8 byte)
 166 {
 167   //  log("Writing %02x at %08x\n", byte, address);
 168   //  log("Current state is %d\n", flashState);
 169   address &= 0xFFFF;
 170   switch(flashState) {
 171   case FLASH_READ_ARRAY:
 172     if(address == 0x5555 && byte == 0xAA)
 173       flashState = FLASH_CMD_1;
 174     break;
 175   case FLASH_CMD_1:
 176     if(address == 0x2AAA && byte == 0x55)
 177       flashState = FLASH_CMD_2;
 178     else
 179       flashState = FLASH_READ_ARRAY;
 180     break;
 181   case FLASH_CMD_2:
 182     if(address == 0x5555) {
 183       if(byte == 0x90) {
 184         flashState = FLASH_AUTOSELECT;
 185         flashReadState = FLASH_AUTOSELECT;
 186       } else if(byte == 0x80) {
 187         flashState = FLASH_CMD_3;
 188       } else if(byte == 0xF0) {
 189         flashState = FLASH_READ_ARRAY;
 190         flashReadState = FLASH_READ_ARRAY;
 191       } else if(byte == 0xA0) {
 192         flashState = FLASH_PROGRAM;
 193       } else if(byte == 0xB0 && flashSize == 0x20000) {
 194         flashState = FLASH_SETBANK;
 195       } else {
 196         flashState = FLASH_READ_ARRAY;
 197         flashReadState = FLASH_READ_ARRAY;
 198       }
 199     } else {
 200       flashState = FLASH_READ_ARRAY;
 201       flashReadState = FLASH_READ_ARRAY;
 202     }
 203     break;
 204   case FLASH_CMD_3:
 205     if(address == 0x5555 && byte == 0xAA) {
 206       flashState = FLASH_CMD_4;
 207     } else {
 208       flashState = FLASH_READ_ARRAY;
 209       flashReadState = FLASH_READ_ARRAY;
 210     }
 211     break;
 212   case FLASH_CMD_4:
 213     if(address == 0x2AAA && byte == 0x55) {
 214       flashState = FLASH_CMD_5;
 215     } else {
 216       flashState = FLASH_READ_ARRAY;
 217       flashReadState = FLASH_READ_ARRAY;
 218     }
 219     break;
 220   case FLASH_CMD_5:
 221     if(byte == 0x30) {
 222       // SECTOR ERASE
 223       memset(&flashSaveMemory[(flashBank << 16) + (address & 0xF000)],
 224              0,
 225              0x1000);
 226       systemSaveUpdateCounter = SYSTEM_SAVE_UPDATED;
 227       flashReadState = FLASH_ERASE_COMPLETE;
 228     } else if(byte == 0x10) {
 229       // CHIP ERASE
 230       memset(flashSaveMemory, 0, flashSize);
 231       systemSaveUpdateCounter = SYSTEM_SAVE_UPDATED;
 232       flashReadState = FLASH_ERASE_COMPLETE;
 233     } else {
 234       flashState = FLASH_READ_ARRAY;
 235       flashReadState = FLASH_READ_ARRAY;
 236     }
 237     break;
 238   case FLASH_AUTOSELECT:
 239     if(byte == 0xF0) {
 240       flashState = FLASH_READ_ARRAY;
 241       flashReadState = FLASH_READ_ARRAY;
 242     } else if(address == 0x5555 && byte == 0xAA)
 243       flashState = FLASH_CMD_1;
 244     else {
 245       flashState = FLASH_READ_ARRAY;
 246       flashReadState = FLASH_READ_ARRAY;
 247     }
 248     break;
 249   case FLASH_PROGRAM:
 250     flashSaveMemory[(flashBank<<16)+address] = byte;
 251     systemSaveUpdateCounter = SYSTEM_SAVE_UPDATED;
 252     flashState = FLASH_READ_ARRAY;
 253     flashReadState = FLASH_READ_ARRAY;
 254     break;
 255   case FLASH_SETBANK:
 256     if(address == 0) {
 257       flashBank = (byte & 1);
 258     }
 259     flashState = FLASH_READ_ARRAY;
 260     flashReadState = FLASH_READ_ARRAY;
 261     break;
 262   }
 263 }