| 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 Lesser General Public |
| 7 | License as published by the Free Software Foundation; either |
| 8 | version 2.1 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 | Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public |
| 16 | License along with this library; if not, write to the Free Software |
| 17 | Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 18 | |
| 19 | Sam Lantinga |
| 20 | slouken@libsdl.org |
| 21 | |
| 22 | */ |
| 23 | #include "SDL_config.h" |
| 24 | |
| 25 | /* Output dreamcast aica */ |
| 26 | |
| 27 | #include "SDL_timer.h" |
| 28 | #include "SDL_audio.h" |
| 29 | #include "../SDL_audiomem.h" |
| 30 | #include "../SDL_audio_c.h" |
| 31 | #include "../SDL_audiodev_c.h" |
| 32 | #include "SDL_dcaudio.h" |
| 33 | |
| 34 | #include "aica.h" |
| 35 | #include <dc/spu.h> |
| 36 | |
| 37 | /* Audio driver functions */ |
| 38 | static int DCAUD_OpenAudio(_THIS, SDL_AudioSpec *spec); |
| 39 | static void DCAUD_WaitAudio(_THIS); |
| 40 | static void DCAUD_PlayAudio(_THIS); |
| 41 | static Uint8 *DCAUD_GetAudioBuf(_THIS); |
| 42 | static void DCAUD_CloseAudio(_THIS); |
| 43 | |
| 44 | /* Audio driver bootstrap functions */ |
| 45 | static int DCAUD_Available(void) |
| 46 | { |
| 47 | return 1; |
| 48 | } |
| 49 | |
| 50 | static void DCAUD_DeleteDevice(SDL_AudioDevice *device) |
| 51 | { |
| 52 | SDL_free(device->hidden); |
| 53 | SDL_free(device); |
| 54 | } |
| 55 | |
| 56 | static SDL_AudioDevice *DCAUD_CreateDevice(int devindex) |
| 57 | { |
| 58 | SDL_AudioDevice *this; |
| 59 | |
| 60 | /* Initialize all variables that we clean on shutdown */ |
| 61 | this = (SDL_AudioDevice *)SDL_malloc(sizeof(SDL_AudioDevice)); |
| 62 | if ( this ) { |
| 63 | SDL_memset(this, 0, (sizeof *this)); |
| 64 | this->hidden = (struct SDL_PrivateAudioData *) |
| 65 | SDL_malloc((sizeof *this->hidden)); |
| 66 | } |
| 67 | if ( (this == NULL) || (this->hidden == NULL) ) { |
| 68 | SDL_OutOfMemory(); |
| 69 | if ( this ) { |
| 70 | SDL_free(this); |
| 71 | } |
| 72 | return(0); |
| 73 | } |
| 74 | SDL_memset(this->hidden, 0, (sizeof *this->hidden)); |
| 75 | |
| 76 | /* Set the function pointers */ |
| 77 | this->OpenAudio = DCAUD_OpenAudio; |
| 78 | this->WaitAudio = DCAUD_WaitAudio; |
| 79 | this->PlayAudio = DCAUD_PlayAudio; |
| 80 | this->GetAudioBuf = DCAUD_GetAudioBuf; |
| 81 | this->CloseAudio = DCAUD_CloseAudio; |
| 82 | |
| 83 | this->free = DCAUD_DeleteDevice; |
| 84 | |
| 85 | spu_init(); |
| 86 | |
| 87 | return this; |
| 88 | } |
| 89 | |
| 90 | AudioBootStrap DCAUD_bootstrap = { |
| 91 | "dcaudio", "Dreamcast AICA audio", |
| 92 | DCAUD_Available, DCAUD_CreateDevice |
| 93 | }; |
| 94 | |
| 95 | /* This function waits until it is possible to write a full sound buffer */ |
| 96 | static void DCAUD_WaitAudio(_THIS) |
| 97 | { |
| 98 | if (this->hidden->playing) { |
| 99 | /* wait */ |
| 100 | while(aica_get_pos(0)/this->spec.samples == this->hidden->nextbuf) { |
| 101 | thd_pass(); |
| 102 | } |
| 103 | } |
| 104 | } |
| 105 | |
| 106 | #define SPU_RAM_BASE 0xa0800000 |
| 107 | |
| 108 | static void spu_memload_stereo8(int leftpos,int rightpos,void *src0,size_t size) |
| 109 | { |
| 110 | uint8 *src = src0; |
| 111 | uint32 *left = (uint32*)(leftpos +SPU_RAM_BASE); |
| 112 | uint32 *right = (uint32*)(rightpos+SPU_RAM_BASE); |
| 113 | size = (size+7)/8; |
| 114 | while(size--) { |
| 115 | unsigned lval,rval; |
| 116 | lval = *src++; |
| 117 | rval = *src++; |
| 118 | lval|= (*src++)<<8; |
| 119 | rval|= (*src++)<<8; |
| 120 | lval|= (*src++)<<16; |
| 121 | rval|= (*src++)<<16; |
| 122 | lval|= (*src++)<<24; |
| 123 | rval|= (*src++)<<24; |
| 124 | g2_write_32(left++,lval); |
| 125 | g2_write_32(right++,rval); |
| 126 | g2_fifo_wait(); |
| 127 | } |
| 128 | } |
| 129 | |
| 130 | static void spu_memload_stereo16(int leftpos,int rightpos,void *src0,size_t size) |
| 131 | { |
| 132 | uint16 *src = src0; |
| 133 | uint32 *left = (uint32*)(leftpos +SPU_RAM_BASE); |
| 134 | uint32 *right = (uint32*)(rightpos+SPU_RAM_BASE); |
| 135 | size = (size+7)/8; |
| 136 | while(size--) { |
| 137 | unsigned lval,rval; |
| 138 | lval = *src++; |
| 139 | rval = *src++; |
| 140 | lval|= (*src++)<<16; |
| 141 | rval|= (*src++)<<16; |
| 142 | g2_write_32(left++,lval); |
| 143 | g2_write_32(right++,rval); |
| 144 | g2_fifo_wait(); |
| 145 | } |
| 146 | } |
| 147 | |
| 148 | static void DCAUD_PlayAudio(_THIS) |
| 149 | { |
| 150 | SDL_AudioSpec *spec = &this->spec; |
| 151 | unsigned int offset; |
| 152 | |
| 153 | if (this->hidden->playing) { |
| 154 | /* wait */ |
| 155 | while(aica_get_pos(0)/spec->samples == this->hidden->nextbuf) { |
| 156 | thd_pass(); |
| 157 | } |
| 158 | } |
| 159 | |
| 160 | offset = this->hidden->nextbuf*spec->size; |
| 161 | this->hidden->nextbuf^=1; |
| 162 | /* Write the audio data, checking for EAGAIN on broken audio drivers */ |
| 163 | if (spec->channels==1) { |
| 164 | spu_memload(this->hidden->leftpos+offset,this->hidden->mixbuf,this->hidden->mixlen); |
| 165 | } else { |
| 166 | offset/=2; |
| 167 | if ((this->spec.format&255)==8) { |
| 168 | spu_memload_stereo8(this->hidden->leftpos+offset,this->hidden->rightpos+offset,this->hidden->mixbuf,this->hidden->mixlen); |
| 169 | } else { |
| 170 | spu_memload_stereo16(this->hidden->leftpos+offset,this->hidden->rightpos+offset,this->hidden->mixbuf,this->hidden->mixlen); |
| 171 | } |
| 172 | } |
| 173 | |
| 174 | if (!this->hidden->playing) { |
| 175 | int mode; |
| 176 | this->hidden->playing = 1; |
| 177 | mode = (spec->format==AUDIO_S8)?SM_8BIT:SM_16BIT; |
| 178 | if (spec->channels==1) { |
| 179 | aica_play(0,mode,this->hidden->leftpos,0,spec->samples*2,spec->freq,255,128,1); |
| 180 | } else { |
| 181 | aica_play(0,mode,this->hidden->leftpos ,0,spec->samples*2,spec->freq,255,0,1); |
| 182 | aica_play(1,mode,this->hidden->rightpos,0,spec->samples*2,spec->freq,255,255,1); |
| 183 | } |
| 184 | } |
| 185 | } |
| 186 | |
| 187 | static Uint8 *DCAUD_GetAudioBuf(_THIS) |
| 188 | { |
| 189 | return(this->hidden->mixbuf); |
| 190 | } |
| 191 | |
| 192 | static void DCAUD_CloseAudio(_THIS) |
| 193 | { |
| 194 | aica_stop(0); |
| 195 | if (this->spec.channels==2) aica_stop(1); |
| 196 | if ( this->hidden->mixbuf != NULL ) { |
| 197 | SDL_FreeAudioMem(this->hidden->mixbuf); |
| 198 | this->hidden->mixbuf = NULL; |
| 199 | } |
| 200 | } |
| 201 | |
| 202 | static int DCAUD_OpenAudio(_THIS, SDL_AudioSpec *spec) |
| 203 | { |
| 204 | Uint16 test_format = SDL_FirstAudioFormat(spec->format); |
| 205 | int valid_datatype = 0; |
| 206 | while ((!valid_datatype) && (test_format)) { |
| 207 | spec->format = test_format; |
| 208 | switch (test_format) { |
| 209 | /* only formats Dreamcast accepts... */ |
| 210 | case AUDIO_S8: |
| 211 | case AUDIO_S16LSB: |
| 212 | valid_datatype = 1; |
| 213 | break; |
| 214 | |
| 215 | default: |
| 216 | test_format = SDL_NextAudioFormat(); |
| 217 | break; |
| 218 | } |
| 219 | } |
| 220 | |
| 221 | if (!valid_datatype) { /* shouldn't happen, but just in case... */ |
| 222 | SDL_SetError("Unsupported audio format"); |
| 223 | return (-1); |
| 224 | } |
| 225 | |
| 226 | if (spec->channels > 2) |
| 227 | spec->channels = 2; /* no more than stereo on the Dreamcast. */ |
| 228 | |
| 229 | /* Update the fragment size as size in bytes */ |
| 230 | SDL_CalculateAudioSpec(spec); |
| 231 | |
| 232 | /* Allocate mixing buffer */ |
| 233 | this->hidden->mixlen = spec->size; |
| 234 | this->hidden->mixbuf = (Uint8 *) SDL_AllocAudioMem(this->hidden->mixlen); |
| 235 | if ( this->hidden->mixbuf == NULL ) { |
| 236 | return(-1); |
| 237 | } |
| 238 | SDL_memset(this->hidden->mixbuf, spec->silence, spec->size); |
| 239 | this->hidden->leftpos = 0x11000; |
| 240 | this->hidden->rightpos = 0x11000+spec->size; |
| 241 | this->hidden->playing = 0; |
| 242 | this->hidden->nextbuf = 0; |
| 243 | |
| 244 | /* We're ready to rock and roll. :-) */ |
| 245 | return(0); |
| 246 | } |