--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/audio/dc/SDL_dcaudio.c	Sat Oct 05 16:50:56 2002 +0000
@@ -0,0 +1,245 @@
+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002  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);
+}