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view src/audio/dc/SDL_dcaudio.c @ 803:355632dca928
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author | Sam Lantinga <slouken@libsdl.org> |
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date | Tue, 10 Feb 2004 15:15:40 +0000 |
parents | b8d311d90021 |
children | c9b51268668f |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2004 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with this library; if not, write to the Free Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA BERO <bero@geocities.co.jp> based on SDL_diskaudio.c by Sam Lantinga <slouken@libsdl.org> */ #ifdef SAVE_RCSID static char rcsid = "@(#) $Id$"; #endif /* Output dreamcast aica */ #include <stdlib.h> #include <stdio.h> #include <string.h> #include <errno.h> #include <unistd.h> #include <sys/stat.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include "SDL_audio.h" #include "SDL_error.h" #include "SDL_audiomem.h" #include "SDL_audio_c.h" #include "SDL_timer.h" #include "SDL_audiodev_c.h" #include "SDL_dcaudio.h" #include "aica.h" #include <dc/spu.h> /* Audio driver functions */ static int DCAUD_OpenAudio(_THIS, SDL_AudioSpec *spec); static void DCAUD_WaitAudio(_THIS); static void DCAUD_PlayAudio(_THIS); static Uint8 *DCAUD_GetAudioBuf(_THIS); static void DCAUD_CloseAudio(_THIS); /* Audio driver bootstrap functions */ static int DCAUD_Available(void) { return 1; } static void DCAUD_DeleteDevice(SDL_AudioDevice *device) { free(device->hidden); free(device); } static SDL_AudioDevice *DCAUD_CreateDevice(int devindex) { SDL_AudioDevice *this; /* Initialize all variables that we clean on shutdown */ this = (SDL_AudioDevice *)malloc(sizeof(SDL_AudioDevice)); if ( this ) { memset(this, 0, (sizeof *this)); this->hidden = (struct SDL_PrivateAudioData *) malloc((sizeof *this->hidden)); } if ( (this == NULL) || (this->hidden == NULL) ) { SDL_OutOfMemory(); if ( this ) { free(this); } return(0); } memset(this->hidden, 0, (sizeof *this->hidden)); /* Set the function pointers */ this->OpenAudio = DCAUD_OpenAudio; this->WaitAudio = DCAUD_WaitAudio; this->PlayAudio = DCAUD_PlayAudio; this->GetAudioBuf = DCAUD_GetAudioBuf; this->CloseAudio = DCAUD_CloseAudio; this->free = DCAUD_DeleteDevice; spu_init(); return this; } AudioBootStrap DCAUD_bootstrap = { "dcaudio", "Dreamcast AICA audio", DCAUD_Available, DCAUD_CreateDevice }; /* This function waits until it is possible to write a full sound buffer */ static void DCAUD_WaitAudio(_THIS) { if (this->hidden->playing) { /* wait */ while(aica_get_pos(0)/this->spec.samples == this->hidden->nextbuf) { thd_pass(); } } } #define SPU_RAM_BASE 0xa0800000 static void spu_memload_stereo8(int leftpos,int rightpos,void *src0,size_t size) { uint8 *src = src0; uint32 *left = (uint32*)(leftpos +SPU_RAM_BASE); uint32 *right = (uint32*)(rightpos+SPU_RAM_BASE); size = (size+7)/8; while(size--) { unsigned lval,rval; lval = *src++; rval = *src++; lval|= (*src++)<<8; rval|= (*src++)<<8; lval|= (*src++)<<16; rval|= (*src++)<<16; lval|= (*src++)<<24; rval|= (*src++)<<24; g2_write_32(left++,lval); g2_write_32(right++,rval); g2_fifo_wait(); } } static void spu_memload_stereo16(int leftpos,int rightpos,void *src0,size_t size) { uint16 *src = src0; uint32 *left = (uint32*)(leftpos +SPU_RAM_BASE); uint32 *right = (uint32*)(rightpos+SPU_RAM_BASE); size = (size+7)/8; while(size--) { unsigned lval,rval; lval = *src++; rval = *src++; lval|= (*src++)<<16; rval|= (*src++)<<16; g2_write_32(left++,lval); g2_write_32(right++,rval); g2_fifo_wait(); } } static void DCAUD_PlayAudio(_THIS) { SDL_AudioSpec *spec = &this->spec; unsigned int offset; if (this->hidden->playing) { /* wait */ while(aica_get_pos(0)/spec->samples == this->hidden->nextbuf) { thd_pass(); } } offset = this->hidden->nextbuf*spec->size; this->hidden->nextbuf^=1; /* Write the audio data, checking for EAGAIN on broken audio drivers */ if (spec->channels==1) { spu_memload(this->hidden->leftpos+offset,this->hidden->mixbuf,this->hidden->mixlen); } else { offset/=2; if ((this->spec.format&255)==8) { spu_memload_stereo8(this->hidden->leftpos+offset,this->hidden->rightpos+offset,this->hidden->mixbuf,this->hidden->mixlen); } else { spu_memload_stereo16(this->hidden->leftpos+offset,this->hidden->rightpos+offset,this->hidden->mixbuf,this->hidden->mixlen); } } if (!this->hidden->playing) { int mode; this->hidden->playing = 1; mode = (spec->format==AUDIO_S8)?SM_8BIT:SM_16BIT; if (spec->channels==1) { aica_play(0,mode,this->hidden->leftpos,0,spec->samples*2,spec->freq,255,128,1); } else { aica_play(0,mode,this->hidden->leftpos ,0,spec->samples*2,spec->freq,255,0,1); aica_play(1,mode,this->hidden->rightpos,0,spec->samples*2,spec->freq,255,255,1); } } } static Uint8 *DCAUD_GetAudioBuf(_THIS) { return(this->hidden->mixbuf); } static void DCAUD_CloseAudio(_THIS) { aica_stop(0); if (this->spec.channels==2) aica_stop(1); if ( this->hidden->mixbuf != NULL ) { SDL_FreeAudioMem(this->hidden->mixbuf); this->hidden->mixbuf = NULL; } } static int DCAUD_OpenAudio(_THIS, SDL_AudioSpec *spec) { switch(spec->format&0xff) { case 8: spec->format = AUDIO_S8; break; case 16: spec->format = AUDIO_S16LSB; break; default: SDL_SetError("Unsupported audio format"); return(-1); } /* Update the fragment size as size in bytes */ SDL_CalculateAudioSpec(spec); /* Allocate mixing buffer */ this->hidden->mixlen = spec->size; this->hidden->mixbuf = (Uint8 *) SDL_AllocAudioMem(this->hidden->mixlen); if ( this->hidden->mixbuf == NULL ) { return(-1); } memset(this->hidden->mixbuf, spec->silence, spec->size); this->hidden->leftpos = 0x11000; this->hidden->rightpos = 0x11000+spec->size; this->hidden->playing = 0; this->hidden->nextbuf = 0; /* We're ready to rock and roll. :-) */ return(0); }