optimizations, fixes, hacks, psp, ...
[picodrive.git] / platform / linux / 940ctl_ym2612.c
index 9702914..ee63458 100644 (file)
 #include "../gp2x/gp2x.h"
 #include "../gp2x/emu.h"
 #include "../gp2x/menu.h"
+#include "../gp2x/code940/940shared.h"
+#include "../common/helix/pub/mp3dec.h"
+#include "../../Pico/PicoInt.h"
 
 
 static YM2612 ym2612;
 
 YM2612 *ym2612_940 = &ym2612;
-int  mix_buffer_[44100/50*2];  /* this is where the YM2612 samples will be mixed to */
-int *mix_buffer = mix_buffer_;
 
+// static _940_data_t  shared_data_;
+static _940_ctl_t   shared_ctl_;
+// static _940_data_t *shared_data = &shared_data_;
+_940_ctl_t  *shared_ctl = &shared_ctl_;
 
-/***********************************************************/
+unsigned char *mp3_mem = 0;
 
-#define MAXOUT         (+32767)
-#define MINOUT         (-32768)
+#define MP3_SIZE_MAX (0x1000000 - 4*640*480)
 
-/* limitter */
-#define Limit(val, max,min) { \
-       if ( val > max )      val = max; \
-       else if ( val < min ) val = min; \
-}
+/***********************************************************/
 
 
 int YM2612Write_940(unsigned int a, unsigned int v)
@@ -40,19 +40,6 @@ int YM2612Write_940(unsigned int a, unsigned int v)
        return 0; // cause the engine to do updates once per frame only
 }
 
-UINT8 YM2612Read_940(void)
-{
-       return YM2612Read_();
-}
-
-
-int YM2612PicoTick_940(int n)
-{
-       YM2612PicoTick_(n);
-
-       return 0;
-}
-
 
 void YM2612PicoStateLoad_940(void)
 {
@@ -71,6 +58,16 @@ void YM2612PicoStateLoad_940(void)
 }
 
 
+void sharedmem_init(void)
+{
+       mp3_mem = malloc(MP3_SIZE_MAX);
+}
+
+void sharedmem_deinit(void)
+{
+       free(mp3_mem);
+}
+
 void YM2612Init_940(int baseclock, int rate)
 {
        YM2612Init_(baseclock, rate);
@@ -83,30 +80,134 @@ void YM2612ResetChip_940(void)
 }
 
 
-void YM2612UpdateOne_940(short *buffer, int length, int stereo)
+#if 0
+static void local_decode(void)
 {
-       int i;
+       int mp3_offs = shared_ctl->mp3_offs;
+       unsigned char *readPtr = mp3_mem + mp3_offs;
+       int bytesLeft = shared_ctl->mp3_len - mp3_offs;
+       int offset; // frame offset from readPtr
+       int err = 0;
+
+       if (bytesLeft <= 0) return; // EOF, nothing to do
+
+       offset = MP3FindSyncWord(readPtr, bytesLeft);
+       if (offset < 0) {
+               shared_ctl->mp3_offs = shared_ctl->mp3_len;
+               return; // EOF
+       }
+       readPtr += offset;
+       bytesLeft -= offset;
+
+       err = MP3Decode(shared_data->mp3dec, &readPtr, &bytesLeft,
+                       shared_data->mp3_buffer[shared_ctl->mp3_buffsel], 0);
+       if (err) {
+               if (err == ERR_MP3_INDATA_UNDERFLOW) {
+                       shared_ctl->mp3_offs = shared_ctl->mp3_len; // EOF
+                       return;
+               } else if (err <= -6 && err >= -12) {
+                       // ERR_MP3_INVALID_FRAMEHEADER, ERR_MP3_INVALID_*
+                       // just try to skip the offending frame..
+                       readPtr++;
+               }
+               shared_ctl->mp3_errors++;
+               shared_ctl->mp3_lasterr = err;
+       }
+       shared_ctl->mp3_offs = readPtr - mp3_mem;
+}
+#endif
+
+
+
 
-       YM2612UpdateOne_(buffer, length, stereo);
-
-       /* mix data */
-       if (stereo) {
-               int *mb = mix_buffer;
-               for (i = length; i > 0; i--) {
-                       int l, r;
-                       l = r = *buffer;
-                       l += *mb++, r += *mb++;
-                       Limit( l, MAXOUT, MINOUT );
-                       Limit( r, MAXOUT, MINOUT );
-                       *buffer++ = l; *buffer++ = r;
+static FILE *loaded_mp3 = 0;
+
+int YM2612UpdateOne_940(int *buffer, int length, int stereo, int is_buf_empty)
+{
+#if 0
+       int cdda_on, *ym_buffer = mix_buffer;
+       static int mp3_samples_ready = 0, mp3_buffer_offs = 0;
+       static int mp3_play_bufsel = 1;
+
+
+       YM2612UpdateOne_(buffer, length, stereo); // really writes to mix_buffer
+
+       // emulatind MCD, not data track, CDC is reading, playback was started, track not ended
+       cdda_on = (PicoMCD & 1) && !(Pico_mcd->s68k_regs[0x36] & 1) && (Pico_mcd->scd.Status_CDC & 1)
+                       && loaded_mp3 && shared_ctl->mp3_offs < shared_ctl->mp3_len;
+
+       /* mix data from previous go */
+       if (cdda_on && mp3_samples_ready >= length)
+       {
+               if (1152 - mp3_buffer_offs >= length) {
+                       mix_samples(buffer, ym_buffer, shared_data->mp3_buffer[mp3_play_bufsel] + mp3_buffer_offs*2, length, stereo);
+
+                       mp3_buffer_offs += length;
+               } else {
+                       // collect from both buffers..
+                       int left = 1152 - mp3_buffer_offs;
+                       mix_samples(buffer, ym_buffer, shared_data->mp3_buffer[mp3_play_bufsel] + mp3_buffer_offs*2, left, stereo);
+                       mp3_play_bufsel ^= 1;
+                       mp3_buffer_offs = length - left;
+                       mix_samples(buffer + left * 2, ym_buffer + left * 2,
+                               shared_data->mp3_buffer[mp3_play_bufsel], mp3_buffer_offs, stereo);
                }
+               mp3_samples_ready -= length;
        } else {
-               for (i = 0; i < length; i++) {
-                       int l = mix_buffer[i];
-                       l += buffer[i];
-                       Limit( l, MAXOUT, MINOUT );
-                       buffer[i] = l;
-               }
+               mix_samples(buffer, ym_buffer, 0, length, stereo);
        }
+
+       // make sure we will have enough mp3 samples next frame
+       if (cdda_on && mp3_samples_ready < length)
+       {
+               shared_ctl->mp3_buffsel ^= 1;
+               local_decode();
+               mp3_samples_ready += 1152;
+       }
+#else
+       return YM2612UpdateOne_(buffer, length, stereo, is_buf_empty);
+#endif
 }
 
+
+void mp3_update(int *buffer, int length, int stereo)
+{
+       // nothing..
+}
+
+
+/***********************************************************/
+
+void mp3_start_play(FILE *f, int pos) // pos is 0-1023
+{
+       int byte_offs = 0;
+
+       if (loaded_mp3 != f)
+       {
+               printf("loading mp3... "); fflush(stdout);
+               fseek(f, 0, SEEK_SET);
+               fread(mp3_mem, 1, MP3_SIZE_MAX, f);
+               if (feof(f)) printf("done.\n");
+               else printf("done. mp3 too large, not all data loaded.\n");
+               shared_ctl->mp3_len = ftell(f);
+               loaded_mp3 = f;
+       }
+
+       // seek..
+       if (pos) {
+               byte_offs  = (shared_ctl->mp3_len << 6) >> 10;
+               byte_offs *= pos;
+               byte_offs >>= 6;
+       }
+       printf("mp3 pos1024: %i, byte_offs %i/%i\n", pos, byte_offs, shared_ctl->mp3_len);
+
+       shared_ctl->mp3_offs = byte_offs;
+}
+
+
+int mp3_get_offset(void)
+{
+       return 0;
+}
+
+