1/*
2    SDL - Simple DirectMedia Layer
3    Copyright (C) 1997-2012 Sam Lantinga
4
5    This library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Library General Public
7    License as published by the Free Software Foundation; either
8    version 2 of the License, or (at your option) any later version.
9
10    This library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Library General Public License for more details.
14
15    You should have received a copy of the GNU Library General Public
16    License along with this library; if not, write to the Free
17    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18
19    Sam Lantinga
20    slouken@libsdl.org
21*/
22#include "SDL_config.h"
23
24/*
25	MiNT audio driver
26	using XBIOS functions (GSXB compatible driver)
27
28	Patrice Mandin
29*/
30
31/* Mint includes */
32#include <mint/osbind.h>
33#include <mint/falcon.h>
34#include <mint/cookie.h>
35
36#include "SDL_audio.h"
37#include "../SDL_audio_c.h"
38#include "../SDL_sysaudio.h"
39
40#include "../../video/ataricommon/SDL_atarimxalloc_c.h"
41
42#include "SDL_mintaudio.h"
43#include "SDL_mintaudio_gsxb.h"
44
45/*--- Defines ---*/
46
47#define MINT_AUDIO_DRIVER_NAME "mint_gsxb"
48
49/* Debug print info */
50#define DEBUG_NAME "audio:gsxb: "
51#if 0
52#define DEBUG_PRINT(what) \
53	{ \
54		printf what; \
55	}
56#else
57#define DEBUG_PRINT(what)
58#endif
59
60/*--- Static variables ---*/
61
62static long cookie_snd, cookie_gsxb;
63
64/*--- Audio driver functions ---*/
65
66static void Mint_CloseAudio(_THIS);
67static int Mint_OpenAudio(_THIS, SDL_AudioSpec *spec);
68static void Mint_LockAudio(_THIS);
69static void Mint_UnlockAudio(_THIS);
70
71/* To check/init hardware audio */
72static int Mint_CheckAudio(_THIS, SDL_AudioSpec *spec);
73static void Mint_InitAudio(_THIS, SDL_AudioSpec *spec);
74
75/* GSXB callbacks */
76static void Mint_GsxbInterrupt(void);
77static void Mint_GsxbNullInterrupt(void);
78
79/*--- Audio driver bootstrap functions ---*/
80
81static int Audio_Available(void)
82{
83	const char *envr = SDL_getenv("SDL_AUDIODRIVER");
84
85	/* Check if user asked a different audio driver */
86	if ((envr) && (SDL_strcmp(envr, MINT_AUDIO_DRIVER_NAME)!=0)) {
87		DEBUG_PRINT((DEBUG_NAME "user asked a different audio driver\n"));
88		return(0);
89	}
90
91	/* Cookie _SND present ? if not, assume ST machine */
92	if (Getcookie(C__SND, &cookie_snd) == C_NOTFOUND) {
93		cookie_snd = SND_PSG;
94	}
95
96	/* Check if we have 16 bits audio */
97	if ((cookie_snd & SND_16BIT)==0) {
98		DEBUG_PRINT((DEBUG_NAME "no 16 bits sound\n"));
99	    return(0);
100	}
101
102	/* Cookie GSXB present ? */
103	cookie_gsxb = (Getcookie(C_GSXB, &cookie_gsxb) == C_FOUND);
104
105	/* Is it GSXB ? */
106	if (((cookie_snd & SND_GSXB)==0) || (cookie_gsxb==0)) {
107		DEBUG_PRINT((DEBUG_NAME "no GSXB audio\n"));
108		return(0);
109	}
110
111	/* Check if audio is lockable */
112	if (Locksnd()!=1) {
113		DEBUG_PRINT((DEBUG_NAME "audio locked by other application\n"));
114		return(0);
115	}
116
117	Unlocksnd();
118
119	DEBUG_PRINT((DEBUG_NAME "GSXB audio available!\n"));
120	return(1);
121}
122
123static void Audio_DeleteDevice(SDL_AudioDevice *device)
124{
125    SDL_free(device->hidden);
126    SDL_free(device);
127}
128
129static SDL_AudioDevice *Audio_CreateDevice(int devindex)
130{
131	SDL_AudioDevice *this;
132
133	/* Initialize all variables that we clean on shutdown */
134	this = (SDL_AudioDevice *)SDL_malloc(sizeof(SDL_AudioDevice));
135    if ( this ) {
136        SDL_memset(this, 0, (sizeof *this));
137        this->hidden = (struct SDL_PrivateAudioData *)
138                SDL_malloc((sizeof *this->hidden));
139    }
140    if ( (this == NULL) || (this->hidden == NULL) ) {
141        SDL_OutOfMemory();
142        if ( this ) {
143            SDL_free(this);
144        }
145        return(0);
146    }
147    SDL_memset(this->hidden, 0, (sizeof *this->hidden));
148
149    /* Set the function pointers */
150    this->OpenAudio   = Mint_OpenAudio;
151    this->CloseAudio  = Mint_CloseAudio;
152    this->LockAudio   = Mint_LockAudio;
153    this->UnlockAudio = Mint_UnlockAudio;
154    this->free        = Audio_DeleteDevice;
155
156    return this;
157}
158
159AudioBootStrap MINTAUDIO_GSXB_bootstrap = {
160	MINT_AUDIO_DRIVER_NAME, "MiNT GSXB audio driver",
161	Audio_Available, Audio_CreateDevice
162};
163
164static void Mint_LockAudio(_THIS)
165{
166	/* Stop replay */
167	Buffoper(0);
168}
169
170static void Mint_UnlockAudio(_THIS)
171{
172	/* Restart replay */
173	Buffoper(SB_PLA_ENA|SB_PLA_RPT);
174}
175
176static void Mint_CloseAudio(_THIS)
177{
178	/* Stop replay */
179	Buffoper(0);
180
181	/* Uninstall interrupt */
182	if (NSetinterrupt(2, SI_NONE, Mint_GsxbNullInterrupt)<0) {
183		DEBUG_PRINT((DEBUG_NAME "NSetinterrupt() failed in close\n"));
184	}
185
186	/* Wait if currently playing sound */
187	while (SDL_MintAudio_mutex != 0) {
188	}
189
190	/* Clear buffers */
191	if (SDL_MintAudio_audiobuf[0]) {
192		Mfree(SDL_MintAudio_audiobuf[0]);
193		SDL_MintAudio_audiobuf[0] = SDL_MintAudio_audiobuf[1] = NULL;
194	}
195
196	/* Unlock sound system */
197	Unlocksnd();
198}
199
200static int Mint_CheckAudio(_THIS, SDL_AudioSpec *spec)
201{
202	long snd_format = 0;
203	int i, resolution, format_signed, format_bigendian;
204    Uint16 test_format = SDL_FirstAudioFormat(spec->format);
205    int valid_datatype = 0;
206
207	resolution = spec->format & 0x00ff;
208	format_signed = ((spec->format & 0x8000)!=0);
209	format_bigendian = ((spec->format & 0x1000)!=0);
210
211	DEBUG_PRINT((DEBUG_NAME "asked: %d bits, ",spec->format & 0x00ff));
212	DEBUG_PRINT(("signed=%d, ", ((spec->format & 0x8000)!=0)));
213	DEBUG_PRINT(("big endian=%d, ", ((spec->format & 0x1000)!=0)));
214	DEBUG_PRINT(("channels=%d, ", spec->channels));
215	DEBUG_PRINT(("freq=%d\n", spec->freq));
216
217    if (spec->channels > 2) {
218        spec->channels = 2;  /* no more than stereo! */
219    }
220
221    while ((!valid_datatype) && (test_format)) {
222        /* Check formats available */
223        snd_format = Sndstatus(SND_QUERYFORMATS);
224        spec->format = test_format;
225        resolution = spec->format & 0xff;
226        format_signed = (spec->format & (1<<15));
227        format_bigendian = (spec->format & (1<<12));
228        switch (test_format) {
229            case AUDIO_U8:
230            case AUDIO_S8:
231                if (snd_format & SND_FORMAT8) {
232                    valid_datatype = 1;
233                    snd_format = Sndstatus(SND_QUERY8BIT);
234                }
235                break;
236
237            case AUDIO_U16LSB:
238            case AUDIO_S16LSB:
239            case AUDIO_U16MSB:
240            case AUDIO_S16MSB:
241                if (snd_format & SND_FORMAT16) {
242                    valid_datatype = 1;
243                    snd_format = Sndstatus(SND_QUERY16BIT);
244                }
245                break;
246
247            default:
248                test_format = SDL_NextAudioFormat();
249                break;
250        }
251    }
252
253    if (!valid_datatype) {
254        SDL_SetError("Unsupported audio format");
255        return (-1);
256    }
257
258	/* Check signed/unsigned format */
259	if (format_signed) {
260		if (snd_format & SND_FORMATSIGNED) {
261			/* Ok */
262		} else if (snd_format & SND_FORMATUNSIGNED) {
263			/* Give unsigned format */
264			spec->format = spec->format & (~0x8000);
265		}
266	} else {
267		if (snd_format & SND_FORMATUNSIGNED) {
268			/* Ok */
269		} else if (snd_format & SND_FORMATSIGNED) {
270			/* Give signed format */
271			spec->format |= 0x8000;
272		}
273	}
274
275	if (format_bigendian) {
276		if (snd_format & SND_FORMATBIGENDIAN) {
277			/* Ok */
278		} else if (snd_format & SND_FORMATLITTLEENDIAN) {
279			/* Give little endian format */
280			spec->format = spec->format & (~0x1000);
281		}
282	} else {
283		if (snd_format & SND_FORMATLITTLEENDIAN) {
284			/* Ok */
285		} else if (snd_format & SND_FORMATBIGENDIAN) {
286			/* Give big endian format */
287			spec->format |= 0x1000;
288		}
289	}
290
291	/* Calculate and select the closest frequency */
292	MINTAUDIO_freqcount=0;
293	for (i=1;i<4;i++) {
294		SDL_MintAudio_AddFrequency(this,
295			MASTERCLOCK_44K/(MASTERPREDIV_MILAN*(1<<i)), MASTERCLOCK_44K,
296			(1<<i)-1, -1);
297	}
298
299#if 1
300	for (i=0; i<MINTAUDIO_freqcount; i++) {
301		DEBUG_PRINT((DEBUG_NAME "freq %d: %lu Hz, clock %lu, prediv %d\n",
302			i, MINTAUDIO_frequencies[i].frequency, MINTAUDIO_frequencies[i].masterclock,
303			MINTAUDIO_frequencies[i].predivisor
304		));
305	}
306#endif
307
308	MINTAUDIO_numfreq=SDL_MintAudio_SearchFrequency(this, spec->freq);
309	spec->freq=MINTAUDIO_frequencies[MINTAUDIO_numfreq].frequency;
310
311	DEBUG_PRINT((DEBUG_NAME "obtained: %d bits, ",spec->format & 0x00ff));
312	DEBUG_PRINT(("signed=%d, ", ((spec->format & 0x8000)!=0)));
313	DEBUG_PRINT(("big endian=%d, ", ((spec->format & 0x1000)!=0)));
314	DEBUG_PRINT(("channels=%d, ", spec->channels));
315	DEBUG_PRINT(("freq=%d\n", spec->freq));
316
317	return 0;
318}
319
320static void Mint_InitAudio(_THIS, SDL_AudioSpec *spec)
321{
322	int channels_mode, prediv;
323	void *buffer;
324
325	/* Stop currently playing sound */
326	Buffoper(0);
327
328	/* Set replay tracks */
329	Settracks(0,0);
330	Setmontracks(0);
331
332	/* Select replay format */
333	switch (spec->format & 0xff) {
334		case 8:
335			if (spec->channels==2) {
336				channels_mode=STEREO8;
337			} else {
338				channels_mode=MONO8;
339			}
340			break;
341		case 16:
342			if (spec->channels==2) {
343				channels_mode=STEREO16;
344			} else {
345				channels_mode=MONO16;
346			}
347			break;
348		default:
349			channels_mode=STEREO16;
350			break;
351	}
352	if (Setmode(channels_mode)<0) {
353		DEBUG_PRINT((DEBUG_NAME "Setmode() failed\n"));
354	}
355
356	prediv = MINTAUDIO_frequencies[MINTAUDIO_numfreq].predivisor;
357	Devconnect(DMAPLAY, DAC, CLKEXT, prediv, 1);
358
359	/* Set buffer */
360	buffer = SDL_MintAudio_audiobuf[SDL_MintAudio_numbuf];
361	if (Setbuffer(0, buffer, buffer + spec->size)<0) {
362		DEBUG_PRINT((DEBUG_NAME "Setbuffer() failed\n"));
363	}
364
365	/* Install interrupt */
366	if (NSetinterrupt(2, SI_PLAY, Mint_GsxbInterrupt)<0) {
367		DEBUG_PRINT((DEBUG_NAME "NSetinterrupt() failed\n"));
368	}
369
370	/* Go */
371	Buffoper(SB_PLA_ENA|SB_PLA_RPT);
372	DEBUG_PRINT((DEBUG_NAME "hardware initialized\n"));
373}
374
375static int Mint_OpenAudio(_THIS, SDL_AudioSpec *spec)
376{
377	/* Lock sound system */
378	if (Locksnd()!=1) {
379   	    SDL_SetError("Mint_OpenAudio: Audio system already in use");
380        return(-1);
381	}
382
383	SDL_MintAudio_device = this;
384
385	/* Check audio capabilities */
386	if (Mint_CheckAudio(this, spec)==-1) {
387		return -1;
388	}
389
390	SDL_CalculateAudioSpec(spec);
391
392	/* Allocate memory for audio buffers in DMA-able RAM */
393	DEBUG_PRINT((DEBUG_NAME "buffer size=%d\n", spec->size));
394
395	SDL_MintAudio_audiobuf[0] = Atari_SysMalloc(spec->size *2, MX_STRAM);
396	if (SDL_MintAudio_audiobuf[0]==NULL) {
397		SDL_SetError("MINT_OpenAudio: Not enough memory for audio buffer");
398		return (-1);
399	}
400	SDL_MintAudio_audiobuf[1] = SDL_MintAudio_audiobuf[0] + spec->size ;
401	SDL_MintAudio_numbuf=0;
402	SDL_memset(SDL_MintAudio_audiobuf[0], spec->silence, spec->size *2);
403	SDL_MintAudio_audiosize = spec->size;
404	SDL_MintAudio_mutex = 0;
405
406	DEBUG_PRINT((DEBUG_NAME "buffer 0 at 0x%08x\n", SDL_MintAudio_audiobuf[0]));
407	DEBUG_PRINT((DEBUG_NAME "buffer 1 at 0x%08x\n", SDL_MintAudio_audiobuf[1]));
408
409	SDL_MintAudio_CheckFpu();
410
411	/* Setup audio hardware */
412	Mint_InitAudio(this, spec);
413
414    return(1);	/* We don't use threaded audio */
415}
416
417static void Mint_GsxbInterrupt(void)
418{
419	Uint8 *newbuf;
420
421	if (SDL_MintAudio_mutex)
422		return;
423
424	SDL_MintAudio_mutex=1;
425
426	SDL_MintAudio_numbuf ^= 1;
427	SDL_MintAudio_Callback();
428	newbuf = SDL_MintAudio_audiobuf[SDL_MintAudio_numbuf];
429	Setbuffer(0, newbuf, newbuf + SDL_MintAudio_audiosize);
430
431	SDL_MintAudio_mutex=0;
432}
433
434static void Mint_GsxbNullInterrupt(void)
435{
436}
437