src/audio/mint/SDL_mintaudio_gsxb.c

   1 /*
   2     SDL - Simple DirectMedia Layer
   3     Copyright (C) 1997-2009 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
  62 static unsigned long cookie_snd, cookie_gsxb;
  63
  64 /*--- Audio driver functions ---*/
  65
  66 static void Mint_CloseAudio(_THIS);
  67 static int Mint_OpenAudio(_THIS, SDL_AudioSpec *spec);
  68 static void Mint_LockAudio(_THIS);
  69 static void Mint_UnlockAudio(_THIS);
  70
  71 /* To check/init hardware audio */
  72 static int Mint_CheckAudio(_THIS, SDL_AudioSpec *spec);
  73 static void Mint_InitAudio(_THIS, SDL_AudioSpec *spec);
  74
  75 /* GSXB callbacks */
  76 static void Mint_GsxbInterrupt(void);
  77 static void Mint_GsxbNullInterrupt(void);
  78
  79 /*--- Audio driver bootstrap functions ---*/
  80
  81 static 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
 123 static void Audio_DeleteDevice(SDL_AudioDevice *device)
 124 {
 125     SDL_free(device->hidden);
 126     SDL_free(device);
 127 }
 128
 129 static 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
 159 AudioBootStrap MINTAUDIO_GSXB_bootstrap = {
 160         MINT_AUDIO_DRIVER_NAME, "MiNT GSXB audio driver",
 161         Audio_Available, Audio_CreateDevice
 162 };
 163
 164 static void Mint_LockAudio(_THIS)
 165 {
 166         /* Stop replay */
 167         Buffoper(0);
 168 }
 169
 170 static void Mint_UnlockAudio(_THIS)
 171 {
 172         /* Restart replay */
 173         Buffoper(SB_PLA_ENA|SB_PLA_RPT);
 174 }
 175
 176 static 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
 200 static int Mint_CheckAudio(_THIS, SDL_AudioSpec *spec)
 201 {
 202         long snd_format;
 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
 320 static 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
 375 static 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
 417 static 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
 434 static void Mint_GsxbNullInterrupt(void)
 435 {
 436 }