--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/audio/mint/SDL_mintaudio_xbios.c	Mon Jul 07 19:16:03 2003 +0000
@@ -0,0 +1,319 @@
+/*
+    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
+
+    Sam Lantinga
+    slouken@libsdl.org
+*/
+
+/*
+	MiNT audio driver
+	using XBIOS functions (Falcon)
+
+	Patrice Mandin
+*/
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+/* Mint includes */
+#include <mint/osbind.h>
+#include <mint/falcon.h>
+#include <mint/cookie.h>
+
+#include "SDL_endian.h"
+#include "SDL_audio.h"
+#include "SDL_audio_c.h"
+#include "SDL_audiomem.h"
+#include "SDL_sysaudio.h"
+
+#include "SDL_atarimxalloc_c.h"
+
+#include "SDL_mintaudio.h"
+
+/*--- Defines ---*/
+
+#define MINT_AUDIO_DRIVER_NAME "mint_xbios"
+
+/* Debug print info */
+#define DEBUG_NAME "audio:xbios: "
+#if 0
+#define DEBUG_PRINT(what) \
+	{ \
+		printf what; \
+	}
+#else
+#define DEBUG_PRINT(what)
+#endif
+
+/*--- Static variables ---*/
+
+static unsigned long cookie_snd;
+
+/*--- Audio driver functions ---*/
+
+static void Mint_CloseAudio(_THIS);
+static int Mint_OpenAudio(_THIS, SDL_AudioSpec *spec);
+static void Mint_LockAudio(_THIS);
+static void Mint_UnlockAudio(_THIS);
+
+/* To check/init hardware audio */
+static int Mint_CheckAudio(_THIS, SDL_AudioSpec *spec);
+static void Mint_InitAudio(_THIS, SDL_AudioSpec *spec);
+
+/*--- Audio driver bootstrap functions ---*/
+
+static int Audio_Available(void)
+{
+	const char *envr = getenv("SDL_AUDIODRIVER");
+
+	/* Check if user asked a different audio driver */
+	if ((envr) && (strcmp(envr, MINT_AUDIO_DRIVER_NAME)!=0)) {
+		DEBUG_PRINT((DEBUG_NAME "user asked a different audio driver\n"));
+		return(0);
+	}
+
+	/* Cookie _SND present ? if not, assume ST machine */
+	if (Getcookie(C__SND, &cookie_snd) == C_NOTFOUND) {
+		cookie_snd = SND_PSG;
+	}
+
+	/* Check if we have 16 bits audio */
+	if ((cookie_snd & SND_16BIT)==0) {
+		DEBUG_PRINT((DEBUG_NAME "no 16 bits sound\n"));
+	    return(0);
+	}
+
+	/* Check if audio is lockable */
+	if (Locksnd()!=1) {
+		DEBUG_PRINT((DEBUG_NAME "audio locked by other application\n"));
+		return(0);
+	}
+
+	Unlocksnd();
+
+	DEBUG_PRINT((DEBUG_NAME "XBIOS audio available!\n"));
+	return(1);
+}
+
+static void Audio_DeleteDevice(SDL_AudioDevice *device)
+{
+    free(device->hidden);
+    free(device);
+}
+
+static SDL_AudioDevice *Audio_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   = Mint_OpenAudio;
+    this->CloseAudio  = Mint_CloseAudio;
+    this->LockAudio   = Mint_LockAudio;
+    this->UnlockAudio = Mint_UnlockAudio;
+    this->free        = Audio_DeleteDevice;
+
+    return this;
+}
+
+AudioBootStrap MINTAUDIO_XBIOS_bootstrap = {
+	MINT_AUDIO_DRIVER_NAME, "MiNT XBIOS audio driver",
+	Audio_Available, Audio_CreateDevice
+};
+
+static void Mint_LockAudio(_THIS)
+{
+	/* Stop replay */
+	Buffoper(0);
+}
+
+static void Mint_UnlockAudio(_THIS)
+{
+	/* Restart replay */
+	Buffoper(SB_PLA_ENA|SB_PLA_RPT);
+}
+
+static void Mint_CloseAudio(_THIS)
+{
+	/* Stop replay */
+	Buffoper(0);
+
+	/* Uninstall interrupt */
+	Jdisint(MFP_DMASOUND);
+
+	/* Wait if currently playing sound */
+	while (SDL_MintAudio_mutex != 0) {
+	}
+
+	/* Clear buffers */
+	if (SDL_MintAudio_audiobuf[0]) {
+		Mfree(SDL_MintAudio_audiobuf[0]);
+		SDL_MintAudio_audiobuf[0] = SDL_MintAudio_audiobuf[1] = NULL;
+	}
+
+	/* Unlock sound system */
+	Unlocksnd();
+}
+
+static int Mint_CheckAudio(_THIS, SDL_AudioSpec *spec)
+{
+	int i;
+
+	DEBUG_PRINT((DEBUG_NAME "asked: %d bits, ",spec->format & 0x00ff));
+	DEBUG_PRINT(("signed=%d, ", ((spec->format & 0x8000)!=0)));
+	DEBUG_PRINT(("big endian=%d, ", ((spec->format & 0x8000)!=0)));
+	DEBUG_PRINT(("channels=%d, ", spec->channels));
+	DEBUG_PRINT(("freq=%d\n", spec->freq));
+
+	spec->format |= 0x8000;	/* Audio is always signed */
+	if ((spec->format & 0x00ff)==16) {
+		spec->format |= 0x1000;	/* Audio is always big endian */
+		spec->channels=2;	/* 16 bits always stereo */
+	}
+
+	/* FIXME: check for an external clock */
+	MINTAUDIO_sfreq=1;
+	MINTAUDIO_nfreq=12;
+	for (i=MINTAUDIO_sfreq;i<MINTAUDIO_nfreq;i++) {
+		MINTAUDIO_hardfreq[i]=MASTERCLOCK_FALCON1/(MASTERPREDIV_FALCON*(i+1));
+		DEBUG_PRINT((DEBUG_NAME "calc:freq(%d)=%lu\n", i, MINTAUDIO_hardfreq[i]));
+	}
+
+	MINTAUDIO_numfreq=SDL_MintAudio_SearchFrequency(this, 1, spec->freq);
+	spec->freq=MINTAUDIO_hardfreq[MINTAUDIO_numfreq];
+
+	DEBUG_PRINT((DEBUG_NAME "obtained: %d bits, ",spec->format & 0x00ff));
+	DEBUG_PRINT(("signed=%d, ", ((spec->format & 0x8000)!=0)));
+	DEBUG_PRINT(("big endian=%d, ", ((spec->format & 0x8000)!=0)));
+	DEBUG_PRINT(("channels=%d, ", spec->channels));
+	DEBUG_PRINT(("freq=%d\n", spec->freq));
+
+	return 0;
+}
+
+static void Mint_InitAudio(_THIS, SDL_AudioSpec *spec)
+{
+	int channels_mode;
+	void *buffer;
+
+	/* Stop currently playing sound */
+	Buffoper(0);
+
+	/* Set replay tracks */
+	Settracks(0,0);
+	Setmontracks(0);
+
+	/* Select replay format */
+	channels_mode=STEREO16;
+	switch (spec->format & 0xff) {
+		case 8:
+			if (spec->channels==2) {
+				channels_mode=STEREO8;
+			} else {
+				channels_mode=MONO8;
+			}
+			break;
+	}
+	if (Setmode(channels_mode)<0) {
+		DEBUG_PRINT((DEBUG_NAME "Setmode() failed\n"));
+	}
+
+	/* FIXME: select an external clock */
+
+	Devconnect(DMAPLAY, DAC, CLK25M, MINTAUDIO_numfreq, 1);
+	DEBUG_PRINT((DEBUG_NAME "25.175 MHz clock selected, prescaler %d\n", MINTAUDIO_numfreq));
+
+	/* Set buffer */
+	buffer = SDL_MintAudio_audiobuf[SDL_MintAudio_numbuf];
+	if (Setbuffer(0, buffer, buffer + spec->size)<0) {
+		DEBUG_PRINT((DEBUG_NAME "Setbuffer() failed\n"));
+	}
+	
+	/* Install interrupt */
+	Jdisint(MFP_DMASOUND);
+	Xbtimer(XB_TIMERA, 8, 1, SDL_MintAudio_XbiosInterrupt);
+	Jenabint(MFP_DMASOUND);
+
+	if (Setinterrupt(SI_TIMERA, SI_PLAY)<0) {
+		DEBUG_PRINT((DEBUG_NAME "Setinterrupt() failed\n"));
+	}
+
+	/* Go */
+	Buffoper(SB_PLA_ENA|SB_PLA_RPT);
+	DEBUG_PRINT((DEBUG_NAME "hardware initialized\n"));
+}
+
+static int Mint_OpenAudio(_THIS, SDL_AudioSpec *spec)
+{
+	/* Lock sound system */
+	if (Locksnd()!=1) {
+   	    SDL_SetError("Mint_OpenAudio: Audio system already in use");
+        return(-1);
+	}
+
+	SDL_MintAudio_device = this;
+
+	/* Check audio capabilities */
+	if (Mint_CheckAudio(this, spec)==-1) {
+		return -1;
+	}
+
+	SDL_CalculateAudioSpec(spec);
+
+	/* Allocate memory for audio buffers in DMA-able RAM */
+	spec->size = spec->samples;
+	spec->size *= spec->channels;
+	spec->size *= (spec->format & 0xFF)/8;
+
+	DEBUG_PRINT((DEBUG_NAME "buffer size=%d\n", spec->size));
+
+	SDL_MintAudio_audiobuf[0] = Atari_SysMalloc(spec->size *2, MX_STRAM);
+	if (SDL_MintAudio_audiobuf[0]==NULL) {
+		SDL_SetError("MINT_OpenAudio: Not enough memory for audio buffer");
+		return (-1);
+	}
+	SDL_MintAudio_audiobuf[1] = SDL_MintAudio_audiobuf[0] + spec->size ;
+	SDL_MintAudio_numbuf=0;
+	memset(SDL_MintAudio_audiobuf[0], spec->silence, spec->size *2);
+	SDL_MintAudio_audiosize = spec->size;
+	SDL_MintAudio_mutex = 0;
+
+	DEBUG_PRINT((DEBUG_NAME "buffer 0 at 0x%08x\n", SDL_MintAudio_audiobuf[0]));
+	DEBUG_PRINT((DEBUG_NAME "buffer 1 at 0x%08x\n", SDL_MintAudio_audiobuf[1]));
+
+	/* Setup audio hardware */
+	Mint_InitAudio(this, spec);
+
+    return(1);	/* We don't use threaded audio */
+}