e14743d1 |
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 | } |