distrib/sdl-1.2.12/src/audio/mint/SDL_mintaudio_gsxb.c - platform/external/qemu - Gitiles

 /*
     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

     Sam Lantinga
     slouken@libsdl.org
 */
 #include "SDL_config.h"

 /*
 	MiNT audio driver
 	using XBIOS functions (GSXB compatible driver)

 	Patrice Mandin
 */

 /* Mint includes */
 #include <mint/osbind.h>
 #include <mint/falcon.h>
 #include <mint/cookie.h>

 #include "SDL_audio.h"
 #include "../SDL_audio_c.h"
 #include "../SDL_sysaudio.h"

 #include "../../video/ataricommon/SDL_atarimxalloc_c.h"

 #include "SDL_mintaudio.h"
 #include "SDL_mintaudio_gsxb.h"

 /*--- Defines ---*/

 #define MINT_AUDIO_DRIVER_NAME "mint_gsxb"

 /* Debug print info */
 #define DEBUG_NAME "audio:gsxb: "
 #if 0
 #define DEBUG_PRINT(what) \
 	{ \
 		printf what; \
 	}
 #else
 #define DEBUG_PRINT(what)
 #endif

 /*--- Static variables ---*/

 static unsigned long cookie_snd, cookie_gsxb;

 /*--- 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);

 /* GSXB callbacks */
 static void Mint_GsxbInterrupt(void);
 static void Mint_GsxbNullInterrupt(void);

 /*--- Audio driver bootstrap functions ---*/

 static int Audio_Available(void)
 {
 	const char *envr = SDL_getenv("SDL_AUDIODRIVER");

 	/* Check if user asked a different audio driver */
 	if ((envr) && (SDL_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);
 	}

 	/* Cookie GSXB present ? */
 	cookie_gsxb = (Getcookie(C_GSXB, &cookie_gsxb) == C_FOUND);

 	/* Is it GSXB ? */
 	if (((cookie_snd & SND_GSXB)==0) || (cookie_gsxb==0)) {
 		DEBUG_PRINT((DEBUG_NAME "no GSXB audio\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 "GSXB audio available!\n"));
 	return(1);
 }

 static void Audio_DeleteDevice(SDL_AudioDevice *device)
 {
     SDL_free(device->hidden);
     SDL_free(device);
 }

 static SDL_AudioDevice *Audio_CreateDevice(int devindex)
 {
 	SDL_AudioDevice *this;

 	/* Initialize all variables that we clean on shutdown */
 	this = (SDL_AudioDevice *)SDL_malloc(sizeof(SDL_AudioDevice));
     if ( this ) {
         SDL_memset(this, 0, (sizeof *this));
         this->hidden = (struct SDL_PrivateAudioData *)
                 SDL_malloc((sizeof *this->hidden));
     }
     if ( (this == NULL) || (this->hidden == NULL) ) {
         SDL_OutOfMemory();
         if ( this ) {
             SDL_free(this);
         }
         return(0);
     }
     SDL_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_GSXB_bootstrap = {
 	MINT_AUDIO_DRIVER_NAME, "MiNT GSXB 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 */
 	if (NSetinterrupt(2, SI_NONE, Mint_GsxbNullInterrupt)<0) {
 		DEBUG_PRINT((DEBUG_NAME "NSetinterrupt() failed in close\n"));
 	}

 	/* 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)
 {
 	long snd_format;
 	int i, resolution, format_signed, format_bigendian;
     Uint16 test_format = SDL_FirstAudioFormat(spec->format);
     int valid_datatype = 0;

 	resolution = spec->format & 0x00ff;
 	format_signed = ((spec->format & 0x8000)!=0);
 	format_bigendian = ((spec->format & 0x1000)!=0);

 	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 & 0x1000)!=0)));
 	DEBUG_PRINT(("channels=%d, ", spec->channels));
 	DEBUG_PRINT(("freq=%d\n", spec->freq));

     if (spec->channels > 2) {
         spec->channels = 2;  /* no more than stereo! */
     }

     while ((!valid_datatype) && (test_format)) {
         /* Check formats available */
         snd_format = Sndstatus(SND_QUERYFORMATS);
         spec->format = test_format;
         resolution = spec->format & 0xff;
         format_signed = (spec->format & (1<<15));
         format_bigendian = (spec->format & (1<<12));
         switch (test_format) {
             case AUDIO_U8:
             case AUDIO_S8:
                 if (snd_format & SND_FORMAT8) {
                     valid_datatype = 1;
                     snd_format = Sndstatus(SND_QUERY8BIT);
                 }
                 break;

             case AUDIO_U16LSB:
             case AUDIO_S16LSB:
             case AUDIO_U16MSB:
             case AUDIO_S16MSB:
                 if (snd_format & SND_FORMAT16) {
                     valid_datatype = 1;
                     snd_format = Sndstatus(SND_QUERY16BIT);
                 }
                 break;

             default:
                 test_format = SDL_NextAudioFormat();
                 break;
         }
     }

     if (!valid_datatype) {
         SDL_SetError("Unsupported audio format");
         return (-1);
     }

 	/* Check signed/unsigned format */
 	if (format_signed) {
 		if (snd_format & SND_FORMATSIGNED) {
 			/* Ok */
 		} else if (snd_format & SND_FORMATUNSIGNED) {
 			/* Give unsigned format */
 			spec->format = spec->format & (~0x8000);
 		}
 	} else {
 		if (snd_format & SND_FORMATUNSIGNED) {
 			/* Ok */
 		} else if (snd_format & SND_FORMATSIGNED) {
 			/* Give signed format */
 			spec->format |= 0x8000;
 		}
 	}

 	if (format_bigendian) {
 		if (snd_format & SND_FORMATBIGENDIAN) {
 			/* Ok */
 		} else if (snd_format & SND_FORMATLITTLEENDIAN) {
 			/* Give little endian format */
 			spec->format = spec->format & (~0x1000);
 		}
 	} else {
 		if (snd_format & SND_FORMATLITTLEENDIAN) {
 			/* Ok */
 		} else if (snd_format & SND_FORMATBIGENDIAN) {
 			/* Give big endian format */
 			spec->format |= 0x1000;
 		}
 	}

 	/* Calculate and select the closest frequency */
 	MINTAUDIO_freqcount=0;
 	for (i=1;i<4;i++) {
 		SDL_MintAudio_AddFrequency(this,
 			MASTERCLOCK_44K/(MASTERPREDIV_MILAN*(1<<i)), MASTERCLOCK_44K,
 			(1<<i)-1, -1);
 	}

 #if 1
 	for (i=0; i<MINTAUDIO_freqcount; i++) {
 		DEBUG_PRINT((DEBUG_NAME "freq %d: %lu Hz, clock %lu, prediv %d\n",
 			i, MINTAUDIO_frequencies[i].frequency, MINTAUDIO_frequencies[i].masterclock,
 			MINTAUDIO_frequencies[i].predivisor
 		));
 	}
 #endif

 	MINTAUDIO_numfreq=SDL_MintAudio_SearchFrequency(this, spec->freq);
 	spec->freq=MINTAUDIO_frequencies[MINTAUDIO_numfreq].frequency;

 	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 & 0x1000)!=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, prediv;
 	void *buffer;

 	/* Stop currently playing sound */
 	Buffoper(0);

 	/* Set replay tracks */
 	Settracks(0,0);
 	Setmontracks(0);

 	/* Select replay format */
 	switch (spec->format & 0xff) {
 		case 8:
 			if (spec->channels==2) {
 				channels_mode=STEREO8;
 			} else {
 				channels_mode=MONO8;
 			}
 			break;
 		case 16:
 			if (spec->channels==2) {
 				channels_mode=STEREO16;
 			} else {
 				channels_mode=MONO16;
 			}
 			break;
 		default:
 			channels_mode=STEREO16;
 			break;
 	}
 	if (Setmode(channels_mode)<0) {
 		DEBUG_PRINT((DEBUG_NAME "Setmode() failed\n"));
 	}

 	prediv = MINTAUDIO_frequencies[MINTAUDIO_numfreq].predivisor;
 	Devconnect(DMAPLAY, DAC, CLKEXT, prediv, 1);

 	/* 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 */
 	if (NSetinterrupt(2, SI_PLAY, Mint_GsxbInterrupt)<0) {
 		DEBUG_PRINT((DEBUG_NAME "NSetinterrupt() 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 */
 	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;
 	SDL_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]));

 	SDL_MintAudio_CheckFpu();

 	/* Setup audio hardware */
 	Mint_InitAudio(this, spec);

     return(1);	/* We don't use threaded audio */
 }

 static void Mint_GsxbInterrupt(void)
 {
 	Uint8 *newbuf;

 	if (SDL_MintAudio_mutex)
 		return;

 	SDL_MintAudio_mutex=1;

 	SDL_MintAudio_numbuf ^= 1;
 	SDL_MintAudio_Callback();
 	newbuf = SDL_MintAudio_audiobuf[SDL_MintAudio_numbuf];
 	Setbuffer(0, newbuf, newbuf + SDL_MintAudio_audiosize);

 	SDL_MintAudio_mutex=0;
 }

 static void Mint_GsxbNullInterrupt(void)
 {
 }
	/*
	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

	Sam Lantinga
	slouken@libsdl.org
	*/
	#include "SDL_config.h"

	/*
	MiNT audio driver
	using XBIOS functions (GSXB compatible driver)

	Patrice Mandin
	*/

	/* Mint includes */
	#include <mint/osbind.h>
	#include <mint/falcon.h>
	#include <mint/cookie.h>

	#include "SDL_audio.h"
	#include "../SDL_audio_c.h"
	#include "../SDL_sysaudio.h"

	#include "../../video/ataricommon/SDL_atarimxalloc_c.h"

	#include "SDL_mintaudio.h"
	#include "SDL_mintaudio_gsxb.h"

	/--- Defines ---/

	#define MINT_AUDIO_DRIVER_NAME "mint_gsxb"

	/* Debug print info */
	#define DEBUG_NAME "audio:gsxb: "
	#if 0
	#define DEBUG_PRINT(what) \
	{ \
	printf what; \
	}
	#else
	#define DEBUG_PRINT(what)
	#endif

	/--- Static variables ---/

	static unsigned long cookie_snd, cookie_gsxb;

	/--- 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);

	/* GSXB callbacks */
	static void Mint_GsxbInterrupt(void);
	static void Mint_GsxbNullInterrupt(void);

	/--- Audio driver bootstrap functions ---/

	static int Audio_Available(void)
	{
	const char *envr = SDL_getenv("SDL_AUDIODRIVER");

	/* Check if user asked a different audio driver */
	if ((envr) && (SDL_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);
	}

	/* Cookie GSXB present ? */
	cookie_gsxb = (Getcookie(C_GSXB, &cookie_gsxb) == C_FOUND);

	/* Is it GSXB ? */
	if (((cookie_snd & SND_GSXB)==0) \|\| (cookie_gsxb==0)) {
	DEBUG_PRINT((DEBUG_NAME "no GSXB audio\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 "GSXB audio available!\n"));
	return(1);
	}

	static void Audio_DeleteDevice(SDL_AudioDevice *device)
	{
	SDL_free(device->hidden);
	SDL_free(device);
	}

	static SDL_AudioDevice *Audio_CreateDevice(int devindex)
	{
	SDL_AudioDevice *this;

	/* Initialize all variables that we clean on shutdown */
	this = (SDL_AudioDevice *)SDL_malloc(sizeof(SDL_AudioDevice));
	if ( this ) {
	SDL_memset(this, 0, (sizeof *this));
	this->hidden = (struct SDL_PrivateAudioData *)
	SDL_malloc((sizeof *this->hidden));
	}
	if ( (this == NULL) \|\| (this->hidden == NULL) ) {
	SDL_OutOfMemory();
	if ( this ) {
	SDL_free(this);
	}
	return(0);
	}
	SDL_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_GSXB_bootstrap = {
	MINT_AUDIO_DRIVER_NAME, "MiNT GSXB 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 */
	if (NSetinterrupt(2, SI_NONE, Mint_GsxbNullInterrupt)<0) {
	DEBUG_PRINT((DEBUG_NAME "NSetinterrupt() failed in close\n"));
	}

	/* 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)
	{
	long snd_format;
	int i, resolution, format_signed, format_bigendian;
	Uint16 test_format = SDL_FirstAudioFormat(spec->format);
	int valid_datatype = 0;

	resolution = spec->format & 0x00ff;
	format_signed = ((spec->format & 0x8000)!=0);
	format_bigendian = ((spec->format & 0x1000)!=0);

	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 & 0x1000)!=0)));
	DEBUG_PRINT(("channels=%d, ", spec->channels));
	DEBUG_PRINT(("freq=%d\n", spec->freq));

	if (spec->channels > 2) {
	spec->channels = 2; /* no more than stereo! */
	}

	while ((!valid_datatype) && (test_format)) {
	/* Check formats available */
	snd_format = Sndstatus(SND_QUERYFORMATS);
	spec->format = test_format;
	resolution = spec->format & 0xff;
	format_signed = (spec->format & (1<<15));
	format_bigendian = (spec->format & (1<<12));
	switch (test_format) {
	case AUDIO_U8:
	case AUDIO_S8:
	if (snd_format & SND_FORMAT8) {
	valid_datatype = 1;
	snd_format = Sndstatus(SND_QUERY8BIT);
	}
	break;

	case AUDIO_U16LSB:
	case AUDIO_S16LSB:
	case AUDIO_U16MSB:
	case AUDIO_S16MSB:
	if (snd_format & SND_FORMAT16) {
	valid_datatype = 1;
	snd_format = Sndstatus(SND_QUERY16BIT);
	}
	break;

	default:
	test_format = SDL_NextAudioFormat();
	break;
	}
	}

	if (!valid_datatype) {
	SDL_SetError("Unsupported audio format");
	return (-1);
	}

	/* Check signed/unsigned format */
	if (format_signed) {
	if (snd_format & SND_FORMATSIGNED) {
	/* Ok */
	} else if (snd_format & SND_FORMATUNSIGNED) {
	/* Give unsigned format */
	spec->format = spec->format & (~0x8000);
	}
	} else {
	if (snd_format & SND_FORMATUNSIGNED) {
	/* Ok */
	} else if (snd_format & SND_FORMATSIGNED) {
	/* Give signed format */
	spec->format \|= 0x8000;
	}
	}

	if (format_bigendian) {
	if (snd_format & SND_FORMATBIGENDIAN) {
	/* Ok */
	} else if (snd_format & SND_FORMATLITTLEENDIAN) {
	/* Give little endian format */
	spec->format = spec->format & (~0x1000);
	}
	} else {
	if (snd_format & SND_FORMATLITTLEENDIAN) {
	/* Ok */
	} else if (snd_format & SND_FORMATBIGENDIAN) {
	/* Give big endian format */
	spec->format \|= 0x1000;
	}
	}

	/* Calculate and select the closest frequency */
	MINTAUDIO_freqcount=0;
	for (i=1;i<4;i++) {
	SDL_MintAudio_AddFrequency(this,
	MASTERCLOCK_44K/(MASTERPREDIV_MILAN*(1<<i)), MASTERCLOCK_44K,
	(1<<i)-1, -1);
	}

	#if 1
	for (i=0; i<MINTAUDIO_freqcount; i++) {
	DEBUG_PRINT((DEBUG_NAME "freq %d: %lu Hz, clock %lu, prediv %d\n",
	i, MINTAUDIO_frequencies[i].frequency, MINTAUDIO_frequencies[i].masterclock,
	MINTAUDIO_frequencies[i].predivisor
	));
	}
	#endif

	MINTAUDIO_numfreq=SDL_MintAudio_SearchFrequency(this, spec->freq);
	spec->freq=MINTAUDIO_frequencies[MINTAUDIO_numfreq].frequency;

	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 & 0x1000)!=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, prediv;
	void *buffer;

	/* Stop currently playing sound */
	Buffoper(0);

	/* Set replay tracks */
	Settracks(0,0);
	Setmontracks(0);

	/* Select replay format */
	switch (spec->format & 0xff) {
	case 8:
	if (spec->channels==2) {
	channels_mode=STEREO8;
	} else {
	channels_mode=MONO8;
	}
	break;
	case 16:
	if (spec->channels==2) {
	channels_mode=STEREO16;
	} else {
	channels_mode=MONO16;
	}
	break;
	default:
	channels_mode=STEREO16;
	break;
	}
	if (Setmode(channels_mode)<0) {
	DEBUG_PRINT((DEBUG_NAME "Setmode() failed\n"));
	}

	prediv = MINTAUDIO_frequencies[MINTAUDIO_numfreq].predivisor;
	Devconnect(DMAPLAY, DAC, CLKEXT, prediv, 1);

	/* 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 */
	if (NSetinterrupt(2, SI_PLAY, Mint_GsxbInterrupt)<0) {
	DEBUG_PRINT((DEBUG_NAME "NSetinterrupt() 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 */
	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;
	SDL_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]));

	SDL_MintAudio_CheckFpu();

	/* Setup audio hardware */
	Mint_InitAudio(this, spec);

	return(1); /* We don't use threaded audio */
	}

	static void Mint_GsxbInterrupt(void)
	{
	Uint8 *newbuf;

	if (SDL_MintAudio_mutex)
	return;

	SDL_MintAudio_mutex=1;

	SDL_MintAudio_numbuf ^= 1;
	SDL_MintAudio_Callback();
	newbuf = SDL_MintAudio_audiobuf[SDL_MintAudio_numbuf];
	Setbuffer(0, newbuf, newbuf + SDL_MintAudio_audiosize);

	SDL_MintAudio_mutex=0;
	}

	static void Mint_GsxbNullInterrupt(void)
	{
	}