platform/gp2x/code940/940.c

   1 #include "940shared.h"\r
   2 \r
   3 static _940_data_t *shared_data = (_940_data_t *)   0x00100000;\r
   4 static _940_ctl_t  *shared_ctl  = (_940_ctl_t *)    0x00200000;\r
   5 static unsigned char *mp3_data  = (unsigned char *) 0x01000000;\r
   6 YM2612 *ym2612_940;\r
   7 int *mix_buffer;\r
   8 \r
   9 // from init.s\r
  10 void wait_irq(void);\r
  11 void spend_cycles(int c);\r
  12 void cache_clean(void);\r
  13 void cache_clean_flush(void);\r
  14 // this should help to resolve race confition where shared var\r
  15 // is changed by other core just before we update it\r
  16 void set_if_not_changed(int *val, int oldval, int newval);\r
  17 \r
  18 //      asm volatile ("mov r0, #0" ::: "r0");\r
  19 //      asm volatile ("mcr p15, 0, r0, c7, c6,  0" ::: "r0"); /* flush dcache */\r
  20 //      asm volatile ("mcr p15, 0, r0, c7, c10, 4" ::: "r0"); /* drain write buffer */\r
  21 \r
  22 \r
  23 static void mp3_decode(void)\r
  24 {\r
  25         int mp3_offs = shared_ctl->mp3_offs;\r
  26         unsigned char *readPtr = mp3_data + mp3_offs;\r
  27         int bytesLeft = shared_ctl->mp3_len - mp3_offs;\r
  28         int offset; // frame offset from readPtr\r
  29         int err;\r
  30 \r
  31         if (bytesLeft <= 0) return; // EOF, nothing to do\r
  32 \r
  33         offset = MP3FindSyncWord(readPtr, bytesLeft);\r
  34         if (offset < 0) {\r
  35                 set_if_not_changed(&shared_ctl->mp3_offs, mp3_offs, shared_ctl->mp3_len);\r
  36                 return; // EOF\r
  37         }\r
  38         readPtr += offset;\r
  39         bytesLeft -= offset;\r
  40 \r
  41         err = MP3Decode(shared_data->mp3dec, &readPtr, &bytesLeft,\r
  42                         shared_data->mp3_buffer[shared_ctl->mp3_buffsel], 0);\r
  43         if (err) {\r
  44                 if (err == ERR_MP3_INDATA_UNDERFLOW) {\r
  45                         shared_ctl->mp3_offs = shared_ctl->mp3_len; // EOF\r
  46                         set_if_not_changed(&shared_ctl->mp3_offs, mp3_offs, shared_ctl->mp3_len);\r
  47                         return;\r
  48                 } else if (err <= -6 && err >= -12) {\r
  49                         // ERR_MP3_INVALID_FRAMEHEADER, ERR_MP3_INVALID_*\r
  50                         // just try to skip the offending frame..\r
  51                         readPtr++;\r
  52                 }\r
  53                 shared_ctl->mp3_errors++;\r
  54                 shared_ctl->mp3_lasterr = err;\r
  55         }\r
  56         set_if_not_changed(&shared_ctl->mp3_offs, mp3_offs, readPtr - mp3_data);\r
  57 }\r
  58 \r
  59 \r
  60 void Main940(int startvector, int pc_at_irq)\r
  61 {\r
  62         ym2612_940 = &shared_data->ym2612;\r
  63         mix_buffer = shared_data->mix_buffer;\r
  64 \r
  65         // debug\r
  66         shared_ctl->vstarts[startvector]++;\r
  67         shared_ctl->last_irq_pc = pc_at_irq;\r
  68         // asm volatile ("mcr p15, 0, r0, c7, c10, 4" ::: "r0");\r
  69 \r
  70 \r
  71 //      for (;;)\r
  72         {\r
  73                 int job_num = 0;\r
  74 /*\r
  75                 while (!shared_ctl->busy)\r
  76                 {\r
  77                         //shared_ctl->waitc++;\r
  78                         spend_cycles(8*1024);\r
  79                 }\r
  80 */\r
  81 /*\r
  82                 if (!shared_ctl->busy)\r
  83                 {\r
  84                         wait_irq();\r
  85                 }\r
  86                 shared_ctl->lastbusy = shared_ctl->busy;\r
  87 */\r
  88 \r
  89                 for (job_num = 0; job_num < MAX_940JOBS; job_num++)\r
  90                 {\r
  91                         shared_ctl->lastjob = (job_num << 8) | shared_ctl->jobs[job_num];\r
  92 \r
  93                         switch (shared_ctl->jobs[job_num])\r
  94                         {\r
  95                                 case JOB940_INITALL:\r
  96                                         /* ym2612 */\r
  97                                         shared_ctl->writebuff0[0] = shared_ctl->writebuff1[0] = 0xffff;\r
  98                                         YM2612Init_(shared_ctl->baseclock, shared_ctl->rate);\r
  99                                         /* Helix mp3 decoder */\r
 100                                         shared_data->mp3dec = MP3InitDecoder();\r
 101                                         break;\r
 102 \r
 103                                 case JOB940_YM2612RESETCHIP:\r
 104                                         YM2612ResetChip_();\r
 105                                         break;\r
 106 \r
 107                                 case JOB940_PICOSTATELOAD:\r
 108                                         YM2612PicoStateLoad_();\r
 109                                         break;\r
 110 \r
 111                                 case JOB940_YM2612UPDATEONE: {\r
 112                                         int i, dw, *wbuff;\r
 113                                         if (shared_ctl->writebuffsel == 1) {\r
 114                                                 wbuff = (int *) shared_ctl->writebuff1;\r
 115                                         } else {\r
 116                                                 wbuff = (int *) shared_ctl->writebuff0;\r
 117                                         }\r
 118 \r
 119                                         /* playback all writes */\r
 120                                         for (i = 2048/2; i > 0; i--) {\r
 121                                                 UINT16 d;\r
 122                                                 dw = *wbuff++;\r
 123                                                 d = dw;\r
 124                                                 if (d == 0xffff) break;\r
 125                                                 YM2612Write_(d >> 8, d);\r
 126                                                 d = (dw>>16);\r
 127                                                 if (d == 0xffff) break;\r
 128                                                 YM2612Write_(d >> 8, d);\r
 129                                         }\r
 130 \r
 131                                         YM2612UpdateOne_(mix_buffer, shared_ctl->length, shared_ctl->stereo, 1);\r
 132                                         break;\r
 133                                 }\r
 134 \r
 135                                 case JOB940_MP3DECODE:\r
 136                                         mp3_decode();\r
 137                                         break;\r
 138                         }\r
 139                 }\r
 140 \r
 141                 cache_clean();\r
 142 //              asm volatile ("mov r0, #0" ::: "r0");\r
 143 //              asm volatile ("mcr p15, 0, r0, c7, c10, 4" ::: "r0"); /* drain write buffer, should be done on nonbuffered write */\r
 144 //              cache_clean_flush();\r
 145 \r
 146                 shared_ctl->loopc++;\r
 147 \r
 148 //              // shared_ctl->busy = 0; // shared mem is not reliable?\r
 149 \r
 150                 wait_irq();\r
 151         }\r
 152 }\r
 153 \r