platform/gp2x/code940/940.c

   1 // The top-level functions for the ARM940\r
   2 // (c) Copyright 2006-2007, Grazvydas "notaz" Ignotas\r
   3 \r
   4 #include "940shared.h"\r
   5 \r
   6 static _940_data_t *shared_data = (_940_data_t *)   0x00100000;\r
   7 static _940_ctl_t  *shared_ctl  = (_940_ctl_t *)    0x00200000;\r
   8 static unsigned char *mp3_data  = (unsigned char *) 0x00400000;\r
   9 YM2612 *ym2612_940;\r
  10 \r
  11 // from init.s\r
  12 int  wait_get_job(int oldjob);\r
  13 void spend_cycles(int c);\r
  14 void dcache_clean(void);\r
  15 void dcache_clean_flush(void);\r
  16 void drain_wb(void);\r
  17 // this should help to resolve race confition where shared var\r
  18 // is changed by other core just before we update it\r
  19 void set_if_not_changed(int *val, int oldval, int newval);\r
  20 \r
  21 //      asm volatile ("mov r0, #0" ::: "r0");\r
  22 //      asm volatile ("mcr p15, 0, r0, c7, c6,  0" ::: "r0"); /* flush dcache */\r
  23 //      asm volatile ("mcr p15, 0, r0, c7, c10, 4" ::: "r0"); /* drain write buffer */\r
  24 \r
  25 \r
  26 static void mp3_decode(void)\r
  27 {\r
  28         int mp3_offs = shared_ctl->mp3_offs;\r
  29         unsigned char *readPtr = mp3_data + mp3_offs;\r
  30         int bytesLeft = shared_ctl->mp3_len - mp3_offs;\r
  31         int offset; // frame offset from readPtr\r
  32         int err;\r
  33 \r
  34         if (bytesLeft <= 0) return; // EOF, nothing to do\r
  35 \r
  36         offset = MP3FindSyncWord(readPtr, bytesLeft);\r
  37         if (offset < 0) {\r
  38                 set_if_not_changed(&shared_ctl->mp3_offs, mp3_offs, shared_ctl->mp3_len);\r
  39                 return; // EOF\r
  40         }\r
  41         readPtr += offset;\r
  42         bytesLeft -= offset;\r
  43 \r
  44         err = MP3Decode(shared_data->mp3dec, &readPtr, &bytesLeft,\r
  45                         shared_data->mp3_buffer[shared_ctl->mp3_buffsel], 0);\r
  46         if (err) {\r
  47                 if (err == ERR_MP3_INDATA_UNDERFLOW) {\r
  48                         set_if_not_changed(&shared_ctl->mp3_offs, mp3_offs, shared_ctl->mp3_len);\r
  49                         return;\r
  50                 } else if (err <= -6 && err >= -12) {\r
  51                         // ERR_MP3_INVALID_FRAMEHEADER, ERR_MP3_INVALID_*\r
  52                         // just try to skip the offending frame..\r
  53                         readPtr++;\r
  54                 }\r
  55                 shared_ctl->mp3_errors++;\r
  56                 shared_ctl->mp3_lasterr = err;\r
  57         }\r
  58         set_if_not_changed(&shared_ctl->mp3_offs, mp3_offs, readPtr - mp3_data);\r
  59 }\r
  60 \r
  61 static void ym_update(int *ym_buffer)\r
  62 {\r
  63         int i, dw;\r
  64         int two_upds = 0;\r
  65         UINT16 *wbuff;\r
  66 \r
  67         if (shared_ctl->writebuffsel == 1) {\r
  68                 wbuff = shared_ctl->writebuff1;\r
  69         } else {\r
  70                 wbuff = shared_ctl->writebuff0;\r
  71         }\r
  72 \r
  73         /* playback all writes */\r
  74         for (i = 2048/2; i > 0; i--) {\r
  75                 UINT16 d;\r
  76                 dw = *(int *)wbuff;\r
  77                 d = dw;\r
  78                 wbuff++;\r
  79                 if (d == 0xffff) break;\r
  80                 if (d == 0xfffe) { two_upds=1; break; }\r
  81                 YM2612Write_(d >> 8, d);\r
  82                 d = (dw>>16);\r
  83                 wbuff++;\r
  84                 if (d == 0xffff) break;\r
  85                 if (d == 0xfffe) { two_upds=1; break; }\r
  86                 YM2612Write_(d >> 8, d);\r
  87         }\r
  88 \r
  89         if (two_upds) {\r
  90                 int len1 = shared_ctl->length / 2;\r
  91                 shared_ctl->ym_active_chs =\r
  92                         YM2612UpdateOne_(ym_buffer, len1, shared_ctl->stereo, 1);\r
  93 \r
  94                 for (i *= 2; i > 0; i--) {\r
  95                         UINT16 d = *wbuff++;\r
  96                         if (d == 0xffff) break;\r
  97                         YM2612Write_(d >> 8, d);\r
  98                 }\r
  99 \r
 100                 ym_buffer += shared_ctl->stereo ? len1*2 : len1;\r
 101                 len1 = shared_ctl->length - len1;\r
 102 \r
 103                 shared_ctl->ym_active_chs =\r
 104                         YM2612UpdateOne_(ym_buffer, len1, shared_ctl->stereo, 1);\r
 105         } else {\r
 106                 shared_ctl->ym_active_chs =\r
 107                         YM2612UpdateOne_(ym_buffer, shared_ctl->length, shared_ctl->stereo, 1);\r
 108         }\r
 109 }\r
 110 \r
 111 \r
 112 void Main940(void)\r
 113 {\r
 114         int *ym_buffer = shared_data->ym_buffer;\r
 115         int job = 0;\r
 116         ym2612_940 = &shared_data->ym2612;\r
 117 \r
 118 \r
 119         for (;;)\r
 120         {\r
 121                 job = wait_get_job(job);\r
 122 \r
 123                 shared_ctl->lastjob = job;\r
 124 \r
 125                 switch (job)\r
 126                 {\r
 127                         case JOB940_INITALL:\r
 128                                 /* ym2612 */\r
 129                                 shared_ctl->writebuff0[0] = shared_ctl->writebuff1[0] = 0xffff;\r
 130                                 YM2612Init_(shared_ctl->baseclock, shared_ctl->rate);\r
 131                                 /* Helix mp3 decoder */\r
 132                                 shared_data->mp3dec = MP3InitDecoder();\r
 133                                 break;\r
 134 \r
 135                         case JOB940_INVALIDATE_DCACHE:\r
 136                                 drain_wb();\r
 137                                 dcache_clean_flush();\r
 138                                 break;\r
 139 \r
 140                         case JOB940_YM2612RESETCHIP:\r
 141                                 YM2612ResetChip_();\r
 142                                 break;\r
 143 \r
 144                         case JOB940_PICOSTATELOAD:\r
 145                                 YM2612PicoStateLoad_();\r
 146                                 break;\r
 147 \r
 148                         case JOB940_YM2612UPDATEONE:\r
 149                                 ym_update(ym_buffer);\r
 150                                 break;\r
 151 \r
 152                         case JOB940_MP3DECODE:\r
 153                                 mp3_decode();\r
 154                                 break;\r
 155                 }\r
 156 \r
 157                 shared_ctl->loopc++;\r
 158                 dcache_clean();\r
 159         }\r
 160 }\r
 161 \r