/*

    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 DMA 8bits (hardware access)

	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_dma8.h"

/*--- Defines ---*/

#define MINT_AUDIO_DRIVER_NAME "mint_dma8"

/* Debug print info */

#define DEBUG_NAME "audio:dma8: "

#if 0

#define DEBUG_PRINT(what) \

	{ \

		printf what; \

	}

#else

#define DEBUG_PRINT(what)

#endif

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

static unsigned long cookie_snd, cookie_mch;

/*--- 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 = 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 _MCH present ? if not, assume ST machine */

	if (Getcookie(C__MCH, &cookie_mch) == C_NOTFOUND) {

		cookie_mch = MCH_ST;

	}

	/* Cookie _SND present ? if not, assume ST machine */

	if (Getcookie(C__SND, &cookie_snd) == C_NOTFOUND) {

		cookie_snd = SND_PSG;

	}

	/* Check if we have 8 bits audio */

	if ((cookie_snd & SND_8BIT)==0) {

		DEBUG_PRINT((DEBUG_NAME "no 8 bits sound\n"));

	    return(0);

	}

	/* Check if audio is lockable */

	if (cookie_snd & SND_16BIT) {

		if (Locksnd()!=1) {

			DEBUG_PRINT((DEBUG_NAME "audio locked by other application\n"));

			return(0);

		}

		Unlocksnd();

	}

	DEBUG_PRINT((DEBUG_NAME "8 bits 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_DMA8_bootstrap = {

	MINT_AUDIO_DRIVER_NAME, "MiNT DMA 8 bits audio driver",

	Audio_Available, Audio_CreateDevice

};

static void Mint_LockAudio(_THIS)

{

	void *oldpile;

	/* Stop replay */

	oldpile=(void *)Super(0);

	DMAAUDIO_IO.control=0;

	Super(oldpile);

}

static void Mint_UnlockAudio(_THIS)

{

	void *oldpile;

	/* Restart replay */

	oldpile=(void *)Super(0);

	DMAAUDIO_IO.control=3;

	Super(oldpile);

}

static void Mint_CloseAudio(_THIS)

{

	void *oldpile;

	/* Stop replay */

	oldpile=(void *)Super(0);

	DMAAUDIO_IO.control=0;

	Super(oldpile);

	DEBUG_PRINT((DEBUG_NAME "closeaudio: replay stopped\n"));

	/* Disable interrupt */

	Jdisint(MFP_DMASOUND);

	DEBUG_PRINT((DEBUG_NAME "closeaudio: interrupt disabled\n"));

	/* Wait if currently playing sound */

	while (SDL_MintAudio_mutex != 0) {

	}

	DEBUG_PRINT((DEBUG_NAME "closeaudio: no more interrupt running\n"));

	/* Clear buffers */

	if (SDL_MintAudio_audiobuf[0]) {

		Mfree(SDL_MintAudio_audiobuf[0]);

		SDL_MintAudio_audiobuf[0] = SDL_MintAudio_audiobuf[1] = NULL;

	}

	DEBUG_PRINT((DEBUG_NAME "closeaudio: buffers freed\n"));

}

static int Mint_CheckAudio(_THIS, SDL_AudioSpec *spec)

{

	int i, masterprediv, sfreq;

	unsigned long masterclock;

	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;

	/* Check formats available */

	spec->format = AUDIO_S8;

	/* Calculate and select the closest frequency */

	sfreq=0;

	masterclock=MASTERCLOCK_STE;

	masterprediv=MASTERPREDIV_STE;

	switch(cookie_mch>>16) {

/*

		case MCH_STE:

			masterclock=MASTERCLOCK_STE;

			masterprediv=MASTERPREDIV_STE;

			break;

*/

		case MCH_TT:

			masterclock=MASTERCLOCK_TT;

			masterprediv=MASTERPREDIV_TT;

			break;

		case MCH_F30:

		case MCH_ARANYM:

			masterclock=MASTERCLOCK_FALCON1;

			masterprediv=MASTERPREDIV_FALCON;

			sfreq=1;

			break;

	}

	MINTAUDIO_freqcount=0;

	for (i=sfreq;i<4;i++) {

		SDL_MintAudio_AddFrequency(this, masterclock/(masterprediv*(1<<i)),

			masterclock, i-sfreq, -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)

{

	void *oldpile;

	unsigned long buffer;

	unsigned char mode;

	/* Set replay tracks */

	if (cookie_snd & SND_16BIT) {

		Settracks(0,0);

		Setmontracks(0);

	}

	oldpile=(void *)Super(0);

	/* Stop currently playing sound */

	DMAAUDIO_IO.control=0;

	/* Set buffer */

	buffer = (unsigned long) SDL_MintAudio_audiobuf[SDL_MintAudio_numbuf];

	DMAAUDIO_IO.start_high = (buffer>>16) & 255;

	DMAAUDIO_IO.start_mid = (buffer>>8) & 255;

	DMAAUDIO_IO.start_low = buffer & 255;

	buffer += SDL_MintAudio_audiosize;

	DMAAUDIO_IO.end_high = (buffer>>16) & 255;

	DMAAUDIO_IO.end_mid = (buffer>>8) & 255;

	DMAAUDIO_IO.end_low = buffer & 255;

	mode = 3-MINTAUDIO_frequencies[MINTAUDIO_numfreq].predivisor;

	if (spec->channels==1) {

		mode |= 1<<7;

	}

	DMAAUDIO_IO.sound_ctrl = mode;	

	/* Set interrupt */

	Jdisint(MFP_DMASOUND);

	Xbtimer(XB_TIMERA, 8, 1, SDL_MintAudio_Dma8Interrupt);

	Jenabint(MFP_DMASOUND);

	if (cookie_snd & SND_16BIT) {

		if (Setinterrupt(SI_TIMERA, SI_PLAY)<0) {

			DEBUG_PRINT((DEBUG_NAME "Setinterrupt() failed\n"));

		}

	}

	/* Go */

	DMAAUDIO_IO.control = 3;	/* playback + repeat */

	Super(oldpile);

}

static int Mint_OpenAudio(_THIS, SDL_AudioSpec *spec)

{

	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 */

}