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 //
  16 // Private function prototypes
  17 //
  18
  19 void eeprom_set_di(uint32 state);
  20 void eeprom_set_cs(uint32 state);
  21 uint32 eeprom_get_do(void);
  22
  23 #define EE_STATE_START                  1
  24 #define EE_STATE_OP_A                   2
  25 #define EE_STATE_OP_B                   3
  26 #define EE_STATE_0                              4
  27 #define EE_STATE_1                              5
  28 #define EE_STATE_2                              6
  29 #define EE_STATE_3                              7
  30 #define EE_STATE_0_0                    8
  31 #define EE_READ_ADDRESS                 9
  32 #define EE_STATE_0_0_0                  10
  33 #define EE_STATE_0_0_1                  11
  34 #define EE_STATE_0_0_2                  12
  35 #define EE_STATE_0_0_3                  13
  36 #define EE_STATE_0_0_1_0                14
  37 #define EE_READ_DATA                    15
  38 #define EE_STATE_BUSY                   16
  39 #define EE_STATE_1_0                    17
  40 #define EE_STATE_1_1                    18
  41 #define EE_STATE_2_0                    19
  42 #define EE_STATE_3_0                    20
  43
  44 uint16 jerry_ee_state = EE_STATE_START;
  45 uint16 jerry_ee_op = 0;
  46 uint16 jerry_ee_rstate = 0;
  47 uint16 jerry_ee_address_data = 0;
  48 uint16 jerry_ee_address_cnt = 6;
  49 uint16 jerry_ee_data = 0;
  50 uint16 jerry_ee_data_cnt = 16;
  51 uint16 jerry_writes_enabled = 0;
  52 uint16 jerry_ee_direct_jump = 0;
  53 FILE * jerry_ee_fp;
  54 extern char jaguar_boot_dir[1024];
  55
  56
  57 void eeprom_init(void)
  58 {
  59         static char eeprom_filename[1024];
  60
  61         sprintf(eeprom_filename, "%s/%s%08X.eep", jaguar_boot_dir, jaguar_eeproms_path, (unsigned int)jaguar_mainRom_crc32);
  62         jerry_ee_fp = fopen(eeprom_filename, "rb");
  63         if (jerry_ee_fp)
  64         {
  65                 fread(eeprom_ram, 1, 128, jerry_ee_fp);
  66                 fclose(jerry_ee_fp);
  67                 fprintf(log_get(), "eeprom: loaded from %s\n", eeprom_filename);
  68                 jerry_ee_fp = fopen(eeprom_filename, "wrb");
  69         }
  70         else
  71         {
  72                 fprintf(log_get(), "eeprom: creating %s\n", eeprom_filename);
  73                 jerry_ee_fp = fopen(eeprom_filename, "wb");
  74                 if (jerry_ee_fp == NULL)
  75                         fprintf(log_get(), "EEPROM: Could not open/create %s\n", eeprom_filename);
  76         }
  77 }
  78
  79 void eeprom_reset(void)
  80 {
  81         if (jerry_ee_fp == NULL)
  82                 memset(eeprom_ram, 0xFF, 64 * sizeof(uint16));
  83 }
  84
  85 void eeprom_done(void)
  86 {
  87         if (jerry_ee_fp)
  88         {
  89                 fwrite(eeprom_ram, 1, 128, jerry_ee_fp);
  90                 fclose(jerry_ee_fp);
  91         }
  92         else
  93                 fprintf(log_get(),"eeprom: not saved\n");
  94 }
  95
  96 void eeprom_byte_write(uint32 offset, uint8 data)
  97 {
  98         switch (offset)
  99         {
 100         case 0xF14001:
 101                 break;
 102         case 0xF14801:
 103                 eeprom_set_di(data & 0x01);
 104                 break;
 105         case 0xF15001:
 106                 eeprom_set_cs(1);
 107                 break;
 108 //      default: fprintf(log_get(),"eeprom: unmapped 0x%.8x\n",offset); break;
 109         }
 110 }
 111
 112 void eeprom_word_write(uint32 offset, uint16 data)
 113 {
 114         eeprom_byte_write(offset+0, (data >> 8) & 0xFF);
 115         eeprom_byte_write(offset+1, data & 0xFF);
 116 }
 117
 118 uint8 eeprom_byte_read(uint32 offset)
 119 {
 120         switch (offset)
 121         {
 122         case 0xF14001:
 123                 return eeprom_get_do();
 124         case 0xF14801:
 125                 break;
 126         case 0xF15001:
 127                 eeprom_set_cs(1);
 128                 break;
 129 //      default: fprintf(log_get(),"eeprom: unmapped 0x%.8x\n",offset); break;
 130         }
 131
 132         return 0x00;
 133 }
 134
 135 uint16 eeprom_word_read(uint32 offset)
 136 {
 137         return ((uint16)eeprom_byte_read(offset+0) << 8) | eeprom_byte_read(offset+1);
 138 }
 139
 140 void eeprom_set_di(uint32 data)
 141 {
 142 //      fprintf(log_get(),"eeprom: di=%i\n",data);
 143 //      fprintf(log_get(),"eeprom: state %i\n",jerry_ee_state);
 144         switch (jerry_ee_state)
 145         {
 146         case EE_STATE_START:
 147                 jerry_ee_state = EE_STATE_OP_A;
 148                 break;
 149         case EE_STATE_OP_A:
 150                 jerry_ee_op = (data << 1);
 151                 jerry_ee_state = EE_STATE_OP_B;
 152                 break;
 153         case EE_STATE_OP_B:
 154                 jerry_ee_op |= data;
 155                 jerry_ee_direct_jump = 0;
 156 //              fprintf(log_get(),"eeprom: opcode %i\n",jerry_ee_op);
 157                 switch (jerry_ee_op)
 158                 {
 159                 case 0: jerry_ee_state = EE_STATE_0; break;
 160                 case 1: jerry_ee_state = EE_STATE_1; break;
 161                 case 2: jerry_ee_state = EE_STATE_2; break;
 162                 case 3: jerry_ee_state = EE_STATE_3; break;
 163                 }
 164                 eeprom_set_di(data);
 165                 break;
 166         case EE_STATE_0:
 167                 jerry_ee_rstate = EE_STATE_0_0;
 168                 jerry_ee_state = EE_READ_ADDRESS;
 169                 jerry_ee_direct_jump = 1;
 170                 jerry_ee_address_cnt = 6;
 171                 jerry_ee_address_data = 0;
 172                 break;
 173         case EE_STATE_0_0:
 174                 switch ((jerry_ee_address_data >> 4) & 0x03)
 175                 {
 176                 case 0: jerry_ee_state=EE_STATE_0_0_0; break;
 177                 case 1: jerry_ee_state=EE_STATE_0_0_1; break;
 178                 case 2: jerry_ee_state=EE_STATE_0_0_2; break;
 179                 case 3: jerry_ee_state=EE_STATE_0_0_3; break;
 180                 }
 181                 eeprom_set_di(data);
 182                 break;
 183         case EE_STATE_0_0_0:
 184                 // writes disable
 185                 // fprintf(log_get(),"eeprom: read only\n");
 186                 jerry_writes_enabled = 0;
 187                 jerry_ee_state = EE_STATE_START;
 188                 break;
 189         case EE_STATE_0_0_1:
 190                 // writes all
 191                 jerry_ee_rstate = EE_STATE_0_0_1_0;
 192                 jerry_ee_state = EE_READ_DATA;
 193                 jerry_ee_data_cnt = 16;
 194                 jerry_ee_data = 0;
 195                 jerry_ee_direct_jump = 1;
 196                 break;
 197         case EE_STATE_0_0_1_0:
 198                 // fprintf(log_get(),"eeprom: filling eeprom with 0x%.4x\n",data);
 199                 if (jerry_writes_enabled)
 200                         for(int i=0; i<64; i++)
 201                                 eeprom_ram[i] = jerry_ee_data;
 202                 //else
 203                 //      fprintf(log_get(),"eeprom: not writing because read only\n");
 204                 jerry_ee_state = EE_STATE_BUSY;
 205                 break;
 206         case EE_STATE_0_0_2:
 207                 // erase all
 208                 //fprintf(log_get(),"eeprom: erasing eeprom\n");
 209                 if (jerry_writes_enabled)
 210                         for(int i=0; i<64; i++)
 211                                 eeprom_ram[i] = 0xFFFF;
 212
 213                 jerry_ee_state=EE_STATE_BUSY;
 214                 break;
 215         case EE_STATE_0_0_3:
 216                 // writes enable
 217                 //fprintf(log_get(),"eeprom: read/write\n");
 218                 jerry_writes_enabled = 1;
 219                 jerry_ee_state = EE_STATE_START;
 220                 break;
 221         case EE_STATE_1:
 222                 jerry_ee_rstate = EE_STATE_1_0;
 223                 jerry_ee_state = EE_READ_ADDRESS;
 224                 jerry_ee_address_cnt = 6;
 225                 jerry_ee_address_data = 0;
 226                 jerry_ee_direct_jump = 1;
 227                 break;
 228         case EE_STATE_1_0:
 229                 jerry_ee_rstate = EE_STATE_1_1;
 230                 jerry_ee_state = EE_READ_DATA;
 231                 jerry_ee_data_cnt = 16;
 232                 jerry_ee_data = 0;
 233                 jerry_ee_direct_jump = 1;
 234                 break;
 235         case EE_STATE_1_1:
 236                 //fprintf(log_get(),"eeprom: writing 0x%.4x at 0x%.2x\n",jerry_ee_data,jerry_ee_address_data);
 237                 if (jerry_writes_enabled)
 238                         eeprom_ram[jerry_ee_address_data] = jerry_ee_data;
 239                 jerry_ee_state = EE_STATE_BUSY;
 240                 break;
 241         case EE_STATE_2:
 242                 jerry_ee_rstate = EE_STATE_2_0;
 243                 jerry_ee_state = EE_READ_ADDRESS;
 244                 jerry_ee_address_cnt = 6;
 245                 jerry_ee_address_data = 0;
 246                 jerry_ee_data_cnt = 16;
 247                 jerry_ee_data = 0;
 248                 break;
 249         case EE_STATE_3:
 250                 jerry_ee_rstate = EE_STATE_3_0;
 251                 jerry_ee_state = EE_READ_ADDRESS;
 252                 jerry_ee_address_cnt = 6;
 253                 jerry_ee_address_data = 0;
 254                 jerry_ee_direct_jump = 1;
 255                 break;
 256         case EE_STATE_3_0:
 257                 //fprintf(log_get(),"eeprom: erasing 0x%.2x\n",jerry_ee_address_data);
 258                 if (jerry_writes_enabled)
 259                         eeprom_ram[jerry_ee_address_data] = 0xFFFF;
 260                 jerry_ee_state = EE_STATE_BUSY;
 261                 break;
 262         case EE_READ_DATA:
 263                 //fprintf(log_get(),"eeprom:\t\t\t%i bit %i\n",data,jerry_ee_data_cnt-1);
 264                 jerry_ee_data <<= 1;
 265                 jerry_ee_data |= data;
 266                 jerry_ee_data_cnt--;
 267                 if (!jerry_ee_data_cnt)
 268                 {
 269                         jerry_ee_state = jerry_ee_rstate;
 270                         if (jerry_ee_direct_jump)
 271                                 eeprom_set_di(data);
 272                 }
 273                 break;
 274         case EE_READ_ADDRESS:
 275                 jerry_ee_address_data <<= 1;
 276                 jerry_ee_address_data |= data;
 277                 jerry_ee_address_cnt--;
 278 //              fprintf(log_get(),"eeprom:\t%i bits remaining\n",jerry_ee_address_cnt);
 279                 if (!jerry_ee_address_cnt)
 280                 {
 281                         jerry_ee_state = jerry_ee_rstate;
 282                         //fprintf(log_get(),"eeprom:\t\tread address 0x%.2x\n",jerry_ee_address_data);
 283                         if (jerry_ee_direct_jump)
 284                                 eeprom_set_di(data);
 285                 }
 286                 break;
 287         default:
 288                 jerry_ee_state = EE_STATE_OP_A;
 289         }
 290 }
 291
 292 void eeprom_set_cs(uint32 state)
 293 {
 294 //      fprintf(log_get(),"eeprom: cs=%i\n",state);
 295         jerry_ee_state = EE_STATE_START;
 296         jerry_ee_op = 0;
 297         jerry_ee_rstate = 0;
 298         jerry_ee_address_data = 0;
 299         jerry_ee_address_cnt = 6;
 300         jerry_ee_data = 0;
 301         jerry_ee_data_cnt = 16;
 302         jerry_writes_enabled = 1;
 303 }
 304
 305 uint32 eeprom_get_do(void)
 306 {
 307         uint16 data = 1;
 308
 309         switch (jerry_ee_state)
 310         {
 311         case EE_STATE_START:
 312                 data = 1;
 313                 break;
 314         case EE_STATE_BUSY:
 315                 jerry_ee_state = EE_STATE_START;
 316                 data = 0;
 317                 break;
 318         case EE_STATE_2_0:
 319                 jerry_ee_data_cnt--;
 320                 data = (eeprom_ram[jerry_ee_address_data] & (1 << jerry_ee_data_cnt)) >> jerry_ee_data_cnt;
 321                 if (!jerry_ee_data_cnt)
 322                 {
 323                         //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());
 324                         jerry_ee_state = EE_STATE_START;
 325                 }
 326                 break;
 327         }
 328
 329 //      fprintf(log_get(),"eeprom: do=%i\n",data);
 330         return data;
 331 }