Shamusworld >> Repos - virtualjaguar/blob - src/eeprom.cpp

   1 //
   2 // EEPROM handler
   3 //
   4 // by cal2
   5 // GCC/SDL port by Niels Wagenaar (Linux/WIN32) and Caz (BeOS)
   6 // Cleanups by James L. Hammons
   7 //
   8
   9 #include "eeprom.h"
  10
  11 #define eeprom_LOG
  12
  13 static uint16 eeprom_ram[64];
  14
  15 void eeprom_set_di(uint32 state);
  16 void eeprom_set_cs(uint32 state);
  17 uint32 eeprom_get_do(void);
  18
  19 #define EE_STATE_START                  1
  20 #define EE_STATE_OP_A                   2
  21 #define EE_STATE_OP_B                   3
  22 #define EE_STATE_0                              4
  23 #define EE_STATE_1                              5
  24 #define EE_STATE_2                              6
  25 #define EE_STATE_3                              7
  26 #define EE_STATE_0_0                    8
  27 #define EE_READ_ADDRESS                 9
  28 #define EE_STATE_0_0_0                  10
  29 #define EE_STATE_0_0_1                  11
  30 #define EE_STATE_0_0_2                  12
  31 #define EE_STATE_0_0_3                  13
  32 #define EE_STATE_0_0_1_0                14
  33 #define EE_READ_DATA                    15
  34 #define EE_STATE_BUSY                   16
  35 #define EE_STATE_1_0                    17
  36 #define EE_STATE_1_1                    18
  37 #define EE_STATE_2_0                    19
  38 #define EE_STATE_3_0                    20
  39
  40 uint16 jerry_ee_state = EE_STATE_START;
  41 uint16 jerry_ee_op = 0;
  42 uint16 jerry_ee_rstate = 0;
  43 uint16 jerry_ee_address_data = 0;
  44 uint16 jerry_ee_address_cnt = 6;
  45 uint16 jerry_ee_data = 0;
  46 uint16 jerry_ee_data_cnt = 16;
  47 uint16 jerry_writes_enabled = 0;
  48 uint16 jerry_ee_direct_jump = 0;
  49 FILE * jerry_ee_fp;
  50 extern char * jaguar_boot_dir;
  51
  52
  53 void eeprom_init(void)
  54 {
  55         static char eeprom_filename[1024];
  56
  57         sprintf(eeprom_filename, "%s\\%s%08X.eep", jaguar_boot_dir, jaguar_eeproms_path, (unsigned int)jaguar_mainRom_crc32);
  58         jerry_ee_fp = fopen(eeprom_filename, "rb");
  59         if (jerry_ee_fp)
  60         {
  61                 fread(eeprom_ram, 1, 128, jerry_ee_fp);
  62                 fclose(jerry_ee_fp);
  63                 fprintf(log_get(), "eeprom: loaded from %s\n", eeprom_filename);
  64                 jerry_ee_fp = fopen(eeprom_filename, "wrb");
  65         }
  66         else
  67         {
  68                 fprintf(log_get(), "eeprom: creating %s\n", eeprom_filename);
  69                 jerry_ee_fp = fopen(eeprom_filename, "wb");
  70                 if (jerry_ee_fp == NULL)
  71                         fprintf(log_get(), "EEPROM: Could not open/create %s\n", eeprom_filename);
  72         }
  73 }
  74
  75 void eeprom_reset(void)
  76 {
  77         if (jerry_ee_fp == NULL)
  78                 memset(eeprom_ram, 0xFF, 64 * sizeof(uint16));
  79 }
  80
  81 void eeprom_done(void)
  82 {
  83         if (jerry_ee_fp)
  84         {
  85                 fwrite(eeprom_ram, 1, 128, jerry_ee_fp);
  86                 fclose(jerry_ee_fp);
  87         }
  88         else
  89                 fprintf(log_get(),"eeprom: not saved\n");
  90 }
  91
  92 void eeprom_byte_write(uint32 offset, uint8 data)
  93 {
  94         switch (offset)
  95         {
  96         case 0xF14001:
  97                 break;
  98         case 0xF14801:
  99                 eeprom_set_di(data & 0x01);
 100                 break;
 101         case 0xF15001:
 102                 eeprom_set_cs(1);
 103                 break;
 104 //      default: fprintf(log_get(),"eeprom: unmapped 0x%.8x\n",offset); break;
 105         }
 106 }
 107
 108 void eeprom_word_write(uint32 offset, uint16 data)
 109 {
 110         eeprom_byte_write(offset+0, (data >> 8) & 0xFF);
 111         eeprom_byte_write(offset+1, data & 0xFF);
 112 }
 113
 114 uint8 eeprom_byte_read(uint32 offset)
 115 {
 116         switch (offset)
 117         {
 118         case 0xF14001:
 119                 return eeprom_get_do();
 120         case 0xF14801:
 121                 break;
 122         case 0xF15001:
 123                 eeprom_set_cs(1);
 124                 break;
 125 //      default: fprintf(log_get(),"eeprom: unmapped 0x%.8x\n",offset); break;
 126         }
 127
 128         return 0x00;
 129 }
 130
 131 uint16 eeprom_word_read(uint32 offset)
 132 {
 133         return ((uint16)eeprom_byte_read(offset+0) << 8) | eeprom_byte_read(offset+1);
 134 }
 135
 136 void eeprom_set_di(uint32 data)
 137 {
 138 //      fprintf(log_get(),"eeprom: di=%i\n",data);
 139 //      fprintf(log_get(),"eeprom: state %i\n",jerry_ee_state);
 140         switch (jerry_ee_state)
 141         {
 142         case EE_STATE_START:
 143                 jerry_ee_state = EE_STATE_OP_A;
 144                 break;
 145         case EE_STATE_OP_A:
 146                 jerry_ee_op = (data << 1);
 147                 jerry_ee_state = EE_STATE_OP_B;
 148                 break;
 149         case EE_STATE_OP_B:
 150                 jerry_ee_op |= data;
 151                 jerry_ee_direct_jump = 0;
 152 //              fprintf(log_get(),"eeprom: opcode %i\n",jerry_ee_op);
 153                 switch (jerry_ee_op)
 154                 {
 155                 case 0: jerry_ee_state = EE_STATE_0; break;
 156                 case 1: jerry_ee_state = EE_STATE_1; break;
 157                 case 2: jerry_ee_state = EE_STATE_2; break;
 158                 case 3: jerry_ee_state = EE_STATE_3; break;
 159                 }
 160                 eeprom_set_di(data);
 161                 break;
 162         case EE_STATE_0:
 163                 jerry_ee_rstate = EE_STATE_0_0;
 164                 jerry_ee_state = EE_READ_ADDRESS;
 165                 jerry_ee_direct_jump = 1;
 166                 jerry_ee_address_cnt = 6;
 167                 jerry_ee_address_data = 0;
 168                 break;
 169         case EE_STATE_0_0:
 170                 switch ((jerry_ee_address_data >> 4) & 0x03)
 171                 {
 172                 case 0: jerry_ee_state=EE_STATE_0_0_0; break;
 173                 case 1: jerry_ee_state=EE_STATE_0_0_1; break;
 174                 case 2: jerry_ee_state=EE_STATE_0_0_2; break;
 175                 case 3: jerry_ee_state=EE_STATE_0_0_3; break;
 176                 }
 177                 eeprom_set_di(data);
 178                 break;
 179         case EE_STATE_0_0_0:
 180                 // writes disable
 181                 // fprintf(log_get(),"eeprom: read only\n");
 182                 jerry_writes_enabled = 0;
 183                 jerry_ee_state = EE_STATE_START;
 184                 break;
 185         case EE_STATE_0_0_1:
 186                 // writes all
 187                 jerry_ee_rstate = EE_STATE_0_0_1_0;
 188                 jerry_ee_state = EE_READ_DATA;
 189                 jerry_ee_data_cnt = 16;
 190                 jerry_ee_data = 0;
 191                 jerry_ee_direct_jump = 1;
 192                 break;
 193         case EE_STATE_0_0_1_0:
 194                 // fprintf(log_get(),"eeprom: filling eeprom with 0x%.4x\n",data);
 195                 if (jerry_writes_enabled)
 196                         for(int i=0; i<64; i++)
 197                                 eeprom_ram[i] = jerry_ee_data;
 198                 //else
 199                 //      fprintf(log_get(),"eeprom: not writing because read only\n");
 200                 jerry_ee_state = EE_STATE_BUSY;
 201                 break;
 202         case EE_STATE_0_0_2:
 203                 // erase all
 204                 //fprintf(log_get(),"eeprom: erasing eeprom\n");
 205                 if (jerry_writes_enabled)
 206                         for(int i=0; i<64; i++)
 207                                 eeprom_ram[i] = 0xFFFF;
 208
 209                 jerry_ee_state=EE_STATE_BUSY;
 210                 break;
 211         case EE_STATE_0_0_3:
 212                 // writes enable
 213                 //fprintf(log_get(),"eeprom: read/write\n");
 214                 jerry_writes_enabled = 1;
 215                 jerry_ee_state = EE_STATE_START;
 216                 break;
 217         case EE_STATE_1:
 218                 jerry_ee_rstate = EE_STATE_1_0;
 219                 jerry_ee_state = EE_READ_ADDRESS;
 220                 jerry_ee_address_cnt = 6;
 221                 jerry_ee_address_data = 0;
 222                 jerry_ee_direct_jump = 1;
 223                 break;
 224         case EE_STATE_1_0:
 225                 jerry_ee_rstate = EE_STATE_1_1;
 226                 jerry_ee_state = EE_READ_DATA;
 227                 jerry_ee_data_cnt = 16;
 228                 jerry_ee_data = 0;
 229                 jerry_ee_direct_jump = 1;
 230                 break;
 231         case EE_STATE_1_1:
 232                 //fprintf(log_get(),"eeprom: writing 0x%.4x at 0x%.2x\n",jerry_ee_data,jerry_ee_address_data);
 233                 if (jerry_writes_enabled)
 234                         eeprom_ram[jerry_ee_address_data] = jerry_ee_data;
 235                 jerry_ee_state = EE_STATE_BUSY;
 236                 break;
 237         case EE_STATE_2:
 238                 jerry_ee_rstate = EE_STATE_2_0;
 239                 jerry_ee_state = EE_READ_ADDRESS;
 240                 jerry_ee_address_cnt = 6;
 241                 jerry_ee_address_data = 0;
 242                 jerry_ee_data_cnt = 16;
 243                 jerry_ee_data = 0;
 244                 break;
 245         case EE_STATE_3:
 246                 jerry_ee_rstate = EE_STATE_3_0;
 247                 jerry_ee_state = EE_READ_ADDRESS;
 248                 jerry_ee_address_cnt = 6;
 249                 jerry_ee_address_data = 0;
 250                 jerry_ee_direct_jump = 1;
 251                 break;
 252         case EE_STATE_3_0:
 253                 //fprintf(log_get(),"eeprom: erasing 0x%.2x\n",jerry_ee_address_data);
 254                 if (jerry_writes_enabled)
 255                         eeprom_ram[jerry_ee_address_data] = 0xFFFF;
 256                 jerry_ee_state = EE_STATE_BUSY;
 257                 break;
 258         case EE_READ_DATA:
 259                 //fprintf(log_get(),"eeprom:\t\t\t%i bit %i\n",data,jerry_ee_data_cnt-1);
 260                 jerry_ee_data <<= 1;
 261                 jerry_ee_data |= data;
 262                 jerry_ee_data_cnt--;
 263                 if (!jerry_ee_data_cnt)
 264                 {
 265                         jerry_ee_state = jerry_ee_rstate;
 266                         if (jerry_ee_direct_jump)
 267                                 eeprom_set_di(data);
 268                 }
 269                 break;
 270         case EE_READ_ADDRESS:
 271                 jerry_ee_address_data <<= 1;
 272                 jerry_ee_address_data |= data;
 273                 jerry_ee_address_cnt--;
 274 //              fprintf(log_get(),"eeprom:\t%i bits remaining\n",jerry_ee_address_cnt);
 275                 if (!jerry_ee_address_cnt)
 276                 {
 277                         jerry_ee_state = jerry_ee_rstate;
 278                         //fprintf(log_get(),"eeprom:\t\tread address 0x%.2x\n",jerry_ee_address_data);
 279                         if (jerry_ee_direct_jump)
 280                                 eeprom_set_di(data);
 281                 }
 282                 break;
 283         default:
 284                 jerry_ee_state = EE_STATE_OP_A;
 285         }
 286 }
 287
 288 void eeprom_set_cs(uint32 state)
 289 {
 290 //      fprintf(log_get(),"eeprom: cs=%i\n",state);
 291         jerry_ee_state = EE_STATE_START;
 292         jerry_ee_op = 0;
 293         jerry_ee_rstate = 0;
 294         jerry_ee_address_data = 0;
 295         jerry_ee_address_cnt = 6;
 296         jerry_ee_data = 0;
 297         jerry_ee_data_cnt = 16;
 298         jerry_writes_enabled = 1;
 299 }
 300
 301 uint32 eeprom_get_do(void)
 302 {
 303         uint16 data = 1;
 304
 305         switch (jerry_ee_state)
 306         {
 307         case EE_STATE_START:
 308                 data = 1;
 309                 break;
 310         case EE_STATE_BUSY:
 311                 jerry_ee_state = EE_STATE_START;
 312                 data = 0;
 313                 break;
 314         case EE_STATE_2_0:
 315                 jerry_ee_data_cnt--;
 316                 data = (eeprom_ram[jerry_ee_address_data] & (1 << jerry_ee_data_cnt)) >> jerry_ee_data_cnt;
 317                 if (!jerry_ee_data_cnt)
 318                 {
 319                         //fprintf(log_get(),"eeprom: read 0x%.4x at 0x%.2x cpu %i pc=0x%.8x\n",eeprom_ram[jerry_ee_address_data],jerry_ee_address_data,jaguar_cpu_in_exec,s68000readPC());
 320                         jerry_ee_state = EE_STATE_START;
 321                 }
 322                 break;
 323         }
 324
 325 //      fprintf(log_get(),"eeprom: do=%i\n",data);
 326         return data;
 327 }