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