1 /*
2 * Mac bong noise generator. Note - we ought to put a boingy noise
3 * here 8)
4 *
5 * ----------------------------------------------------------------------
6 * 16.11.98:
7 * rewrote some functions, added support for Enhanced ASC (Quadras)
8 * after the NetBSD asc.c console bell patch by Colin Wood/Frederick Bruck
9 * Juergen Mellinger (juergen.mellinger@t-online.de)
10 */
11
12 #include <linux/sched.h>
13 #include <linux/timer.h>
14
15 #include <asm/macintosh.h>
16 #include <asm/mac_asc.h>
17
18 static int mac_asc_inited = 0;
19 /*
20 * dumb triangular wave table
21 */
22 static __u8 mac_asc_wave_tab[ 0x800 ];
23
24 /*
25 * Alan's original sine table; needs interpolating to 0x800
26 * (hint: interpolate or hardwire [0 -> Pi/2[, it's symmetric)
27 */
28 static const signed char sine_data[] = {
29 0, 39, 75, 103, 121, 127, 121, 103, 75, 39,
30 0, -39, -75, -103, -121, -127, -121, -103, -75, -39
31 };
32
33 /*
34 * where the ASC hides ...
35 */
36 static volatile __u8* mac_asc_regs = ( void* )0x50F14000;
37
38 /*
39 * sample rate; is this a good default value?
40 */
41 static unsigned long mac_asc_samplespersec = 11050;
42 static int mac_bell_duration = 0;
43 static unsigned long mac_bell_phase; /* 0..2*Pi -> 0..0x800 (wavetable size) */
44 static unsigned long mac_bell_phasepersample;
45
46 /*
47 * some function protos
48 */
49 static void mac_init_asc( void );
50 static void mac_nosound( unsigned long );
51 static void mac_quadra_start_bell( unsigned int, unsigned int, unsigned int );
52 static void mac_quadra_ring_bell( unsigned long );
53 static void mac_av_start_bell( unsigned int, unsigned int, unsigned int );
54 static void ( *mac_special_bell )( unsigned int, unsigned int, unsigned int ) = NULL;
55
56 /*
57 * our timer to start/continue/stop the bell
58 */
59 static struct timer_list mac_sound_timer = { function: mac_nosound };
60
61 /*
62 * Sort of initialize the sound chip (called from mac_mksound on the first
63 * beep).
64 */
mac_init_asc(void)65 static void mac_init_asc( void )
66 {
67 int i;
68
69 /*
70 * do some machine specific initialization
71 * BTW:
72 * the NetBSD Quadra patch identifies the Enhanced Apple Sound Chip via
73 * mac_asc_regs[ 0x800 ] & 0xF0 != 0
74 * this makes no sense here, because we have to set the default sample
75 * rate anyway if we want correct frequencies
76 */
77 switch ( macintosh_config->ident )
78 {
79 case MAC_MODEL_IIFX:
80 /*
81 * The IIfx is always special ...
82 */
83 mac_asc_regs = ( void* )0x50010000;
84 break;
85 /*
86 * not sure about how correct this list is
87 * machines with the EASC enhanced apple sound chip
88 */
89 case MAC_MODEL_Q630:
90 case MAC_MODEL_P475:
91 mac_special_bell = mac_quadra_start_bell;
92 mac_asc_samplespersec = 22150;
93 break;
94 case MAC_MODEL_C660:
95 case MAC_MODEL_Q840:
96 /*
97 * The Quadra 660AV and 840AV use the "Singer" custom ASIC for sound I/O.
98 * It appears to be similar to the "AWACS" custom ASIC in the Power Mac
99 * [678]100. Because Singer and AWACS may have a similar hardware
100 * interface, this would imply that the code in drivers/sound/dmasound.c
101 * for AWACS could be used as a basis for Singer support. All we have to
102 * do is figure out how to do DMA on the 660AV/840AV through the PSC and
103 * figure out where the Singer hardware sits in memory. (I'd look in the
104 * vicinity of the AWACS location in a Power Mac [678]100 first, or the
105 * current location of the Apple Sound Chip--ASC--in other Macs.) The
106 * Power Mac [678]100 info can be found in MkLinux Mach kernel sources.
107 *
108 * Quoted from Apple's Tech Info Library, article number 16405:
109 * "Among desktop Macintosh computers, only the 660AV, 840AV, and Power
110 * Macintosh models have 16-bit audio input and output capability
111 * because of the AT&T DSP3210 hardware circuitry and the 16-bit Singer
112 * codec circuitry in the AVs. The Audio Waveform Amplifier and
113 * Converter (AWAC) chip in the Power Macintosh performs the same
114 * 16-bit I/O functionality. The PowerBook 500 series computers
115 * support 16-bit stereo output, but only mono input."
116 *
117 * http://til.info.apple.com/techinfo.nsf/artnum/n16405
118 *
119 * --David Kilzer
120 */
121 mac_special_bell = mac_av_start_bell;
122 break;
123 case MAC_MODEL_Q650:
124 case MAC_MODEL_Q700:
125 case MAC_MODEL_Q800:
126 case MAC_MODEL_Q900:
127 case MAC_MODEL_Q950:
128 /*
129 * Currently not implemented!
130 */
131 mac_special_bell = NULL;
132 break;
133 default:
134 /*
135 * Every switch needs a default
136 */
137 mac_special_bell = NULL;
138 break;
139 }
140
141 /*
142 * init the wave table with a simple triangular wave
143 * A sine wave would sure be nicer here ...
144 */
145 for ( i = 0; i < 0x400; i++ )
146 {
147 mac_asc_wave_tab[ i ] = i / 4;
148 mac_asc_wave_tab[ i + 0x400 ] = 0xFF - i / 4;
149 }
150 mac_asc_inited = 1;
151 }
152
153 /*
154 * Called to make noise; current single entry to the boing driver.
155 * Does the job for simple ASC, calls other routines else.
156 * XXX Fixme:
157 * Should be split into asc_mksound, easc_mksound, av_mksound and
158 * function pointer set in mac_init_asc which would be called at
159 * init time.
160 * _This_ is rather ugly ...
161 */
mac_mksound(unsigned int freq,unsigned int length)162 void mac_mksound( unsigned int freq, unsigned int length )
163 {
164 __u32 cfreq = ( freq << 5 ) / 468;
165 __u32 flags;
166 int i;
167
168 if ( mac_special_bell == NULL )
169 {
170 /* Do nothing */
171 return;
172 }
173
174 if ( !mac_asc_inited )
175 mac_init_asc();
176
177 if ( mac_special_bell )
178 {
179 mac_special_bell( freq, length, 128 );
180 return;
181 }
182
183 if ( freq < 20 || freq > 20000 || length == 0 )
184 {
185 mac_nosound( 0 );
186 return;
187 }
188
189 save_flags( flags );
190 cli();
191
192 del_timer( &mac_sound_timer );
193
194 for ( i = 0; i < 0x800; i++ )
195 mac_asc_regs[ i ] = 0;
196 for ( i = 0; i < 0x800; i++ )
197 mac_asc_regs[ i ] = mac_asc_wave_tab[ i ];
198
199 for ( i = 0; i < 8; i++ )
200 *( __u32* )( ( __u32 )mac_asc_regs + ASC_CONTROL + 0x814 + 8 * i ) = cfreq;
201
202 mac_asc_regs[ 0x807 ] = 0;
203 mac_asc_regs[ ASC_VOLUME ] = 128;
204 mac_asc_regs[ 0x805 ] = 0;
205 mac_asc_regs[ 0x80F ] = 0;
206 mac_asc_regs[ ASC_MODE ] = ASC_MODE_SAMPLE;
207 mac_asc_regs[ ASC_ENABLE ] = ASC_ENABLE_SAMPLE;
208
209 mac_sound_timer.expires = jiffies + length;
210 add_timer( &mac_sound_timer );
211
212 restore_flags( flags );
213 }
214
215 /*
216 * regular ASC: stop whining ..
217 */
mac_nosound(unsigned long ignored)218 static void mac_nosound( unsigned long ignored )
219 {
220 mac_asc_regs[ ASC_ENABLE ] = 0;
221 }
222
223 /*
224 * EASC entry; init EASC, don't load wavetable, schedule 'start whining'.
225 */
mac_quadra_start_bell(unsigned int freq,unsigned int length,unsigned int volume)226 static void mac_quadra_start_bell( unsigned int freq, unsigned int length, unsigned int volume )
227 {
228 __u32 flags;
229
230 /* if the bell is already ringing, ring longer */
231 if ( mac_bell_duration > 0 )
232 {
233 mac_bell_duration += length;
234 return;
235 }
236
237 mac_bell_duration = length;
238 mac_bell_phase = 0;
239 mac_bell_phasepersample = ( freq * sizeof( mac_asc_wave_tab ) ) / mac_asc_samplespersec;
240 /* this is reasonably big for small frequencies */
241
242 save_flags( flags );
243 cli();
244
245 /* set the volume */
246 mac_asc_regs[ 0x806 ] = volume;
247
248 /* set up the ASC registers */
249 if ( mac_asc_regs[ 0x801 ] != 1 )
250 {
251 /* select mono mode */
252 mac_asc_regs[ 0x807 ] = 0;
253 /* select sampled sound mode */
254 mac_asc_regs[ 0x802 ] = 0;
255 /* ??? */
256 mac_asc_regs[ 0x801 ] = 1;
257 mac_asc_regs[ 0x803 ] |= 0x80;
258 mac_asc_regs[ 0x803 ] &= 0x7F;
259 }
260
261 mac_sound_timer.function = mac_quadra_ring_bell;
262 mac_sound_timer.expires = jiffies + 1;
263 add_timer( &mac_sound_timer );
264
265 restore_flags( flags );
266 }
267
268 /*
269 * EASC 'start/continue whining'; I'm not sure why the above function didn't
270 * already load the wave table, or at least call this one...
271 * This piece keeps reloading the wave table until done.
272 */
mac_quadra_ring_bell(unsigned long ignored)273 static void mac_quadra_ring_bell( unsigned long ignored )
274 {
275 int i, count = mac_asc_samplespersec / HZ;
276 __u32 flags;
277
278 /*
279 * we neither want a sound buffer overflow nor underflow, so we need to match
280 * the number of samples per timer interrupt as exactly as possible.
281 * using the asc interrupt will give better results in the future
282 * ...and the possibility to use a real sample (a boingy noise, maybe...)
283 */
284
285 save_flags( flags );
286 cli();
287
288 del_timer( &mac_sound_timer );
289
290 if ( mac_bell_duration-- > 0 )
291 {
292 for ( i = 0; i < count; i++ )
293 {
294 mac_bell_phase += mac_bell_phasepersample;
295 mac_asc_regs[ 0 ] = mac_asc_wave_tab[ mac_bell_phase & ( sizeof( mac_asc_wave_tab ) - 1 ) ];
296 }
297 mac_sound_timer.expires = jiffies + 1;
298 add_timer( &mac_sound_timer );
299 }
300 else
301 mac_asc_regs[ 0x801 ] = 0;
302
303 restore_flags( flags );
304 }
305
306 /*
307 * AV code - please fill in.
308 */
mac_av_start_bell(unsigned int freq,unsigned int length,unsigned int volume)309 static void mac_av_start_bell( unsigned int freq, unsigned int length, unsigned int volume )
310 {
311 }
312