1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
|
/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2006 Thom Johansen
* Portions Copyright (C) 2007 Michael Sevakis
*
* All files in this archive are subject to the GNU General Public License.
* See the file COPYING in the source tree root for full license agreement.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
/****************************************************************************
* void dsp_apply_gain(int count, struct dsp_data *data, int32_t *buf[])
*/
.section .text
.align 2
.global dsp_apply_gain
dsp_apply_gain:
lea.l -20(%sp), %sp | save registers
movem.l %d2-%d4/%a2-%a3, (%sp) |
movem.l 28(%sp), %a0-%a1 | %a0 = data,
| %a1 = buf
move.l 4(%a0), %d1 | %d1 = data->num_channels
move.l 32(%a0), %a0 | %a0 = data->gain (in s8.23)
10: | channel loop |
move.l 24(%sp), %d0 | %d0 = count
move.l -4(%a1, %d1.l*4), %a2 | %a2 = s = buf[ch-1]
move.l %a2, %a3 | %a3 = d = s
move.l (%a2)+, %d2 | %d2 = *s++,
mac.l %a0, %d2, (%a2)+, %d2, %acc0 | %acc0 = S(n)*gain, load S(n+1)
subq.l #1, %d0 | --count > 0 ? : effectively n++
ble.b 30f | loop done | no? finish up
20: | loop |
move.l %accext01, %d4 | fetch S(n-1)[7:0]
movclr.l %acc0, %d3 | fetch S(n-1)[40:8] in %d5[31:0]
asl.l #8, %d3 | *s++ = (S(n-1)[40:8] << 8) | S(n-1)[7:0]
mac.l %a0, %d2, (%a2)+, %d2, %acc0 | %acc0 = S(n)*gain, load S(n+1)
move.b %d4, %d3 |
move.l %d3, (%a3)+ |
subq.l #1, %d0 | --count > 0 ? : effectively n++
bgt.b 20b | loop | yes? do more samples
30: | loop done |
move.l %accext01, %d4 | fetch S(n-1)[7:0]
movclr.l %acc0, %d3 | fetch S(n-1)[40:8] in %d5[31:0]
asl.l #8, %d3 | *s = (S(n-1)[40:8] << 8) | S(n-1)[7:0]
move.b %d4, %d3 |
move.l %d3, (%a3) |
subq.l #1, %d1 | next channel
bgt.b 10b | channel loop |
movem.l (%sp), %d2-%d4/%a2-%a3 | restore registers
lea.l 20(%sp), %sp | cleanup stack
rts |
.size dsp_apply_gain,.-dsp_apply_gain
/****************************************************************************
* void apply_crossfeed(int count, int32_t *buf[])
*/
.section .text
.align 2
.global apply_crossfeed
apply_crossfeed:
lea.l -44(%sp), %sp |
movem.l %d2-%d7/%a2-%a6, (%sp) | save all regs
movem.l 48(%sp), %d7/%a4 | %d7 = count, %a4 = src
movem.l (%a4), %a4-%a5 | %a4 = src[0], %a5 = src[1]
lea.l crossfeed_data, %a1 | %a1 = &crossfeed_data
move.l (%a1)+, %d6 | %d6 = direct gain
movem.l 12(%a1), %d0-%d3 | fetch filter history samples
move.l 132(%a1), %a0 | fetch delay line address
movem.l (%a1), %a1-%a3 | load filter coefs
lea.l crossfeed_data+136, %a6 | %a6 = delay line wrap limit
bra.b 20f | loop start | go to loop start point
/* Register usage in loop:
* %a0 = delay_p, %a1..%a3 = b0, b1, a1 (filter coefs),
* %a4 = buf[0], %a5 = buf[1],
* %a6 = delay line pointer wrap limit,
* %d0..%d3 = history
* %d4..%d5 = temp.
* %d6 = direct gain,
* %d7 = count
*/
10: | loop |
movclr.l %acc0, %d4 | write outputs
move.l %d4, (%a4)+ | .
movclr.l %acc1, %d5 | .
move.l %d5, (%a5)+ | .
20: | loop start |
mac.l %a2, %d0, (%a0)+, %d0, %acc0 | %acc0 = b1*dl[n - 1], %d0 = dl[n]
mac.l %a1, %d0 , %acc0 | %acc0 += b0*dl[n]
mac.l %a3, %d1, (%a5), %d5, %acc0 | %acc0 += a1*y_r[n - 1], load R
mac.l %a2, %d2, (%a0)+, %d2, %acc1 | %acc1 = b1*dr[n - 1], %d2 = dr[n]
mac.l %a1, %d2 , %acc1 | %acc1 += b0*dr[n]
mac.l %a3, %d3, (%a4), %d4, %acc1 | %acc1 += a1*y_l[n - 1], load L
movem.l %d4-%d5, -8(%a0) | save left & right inputs to delay line
move.l %acc0, %d3 | get filtered delayed left sample (y_l[n])
move.l %acc1, %d1 | get filtered delayed right sample (y_r[n])
mac.l %d6, %d4, %acc0 | %acc0 += gain*x_l[n]
mac.l %d6, %d5, %acc1 | %acc1 += gain*x_r[n]
cmp.l %a6, %a0 | wrap %a0 if passed end
bhs.b 30f | wrap buffer |
.word 0x51fb | tpf.l | trap the buffer wrap
30: | wrap buffer | ...fwd taken branches more costly
lea.l -104(%a0), %a0 | wrap it up
subq.l #1, %d7 | --count > 0 ?
bgt.b 10b | loop | yes? do more
movclr.l %acc0, %d4 | write last outputs
move.l %d4, (%a4) | .
movclr.l %acc1, %d5 | .
move.l %d5, (%a5) | .
lea.l crossfeed_data+16, %a1 | save data back to struct
movem.l %d0-%d3, (%a1) | ...history
move.l %a0, 120(%a1) | ...delay_p
movem.l (%sp), %d2-%d7/%a2-%a6 | restore all regs
lea.l 44(%sp), %sp |
rts |
.size apply_crossfeed,.-apply_crossfeed
/****************************************************************************
* int dsp_downsample(int count, struct dsp_data *data,
* in32_t *src[], int32_t *dst[])
*/
.section .text
.align 2
.global dsp_downsample
dsp_downsample:
lea.l -40(%sp), %sp | save non-clobberables
movem.l %d2-%d7/%a2-%a5, (%sp) |
movem.l 44(%sp), %d2/%a0-%a2 | %d2 = count
| %a0 = data
| %a1 = src
| %a2 = dst
movem.l 4(%a0), %d3-%d4 | %d3 = ch = data->num_channels
| %d4 = delta = data->resample_data.delta
moveq.l #16, %d7 | %d7 = shift
10: | channel loop |
move.l 12(%a0), %d5 | %d5 = phase = data->resample_data.phase
move.l -4(%a1, %d3.l*4), %a3 | %a3 = s = src[ch-1]
move.l -4(%a2, %d3.l*4), %a4 | %a4 = d = dst[ch-1]
lea.l 12(%a0, %d3.l*4), %a5 | %a5 = &data->resample_data.ast_sample[ch-1]
move.l (%a5), %d0 | %d0 = last = data->resample_data.last_sample[ch-1]
move.l -4(%a3, %d2.l*4), (%a5) | data->resample_data.last_sample[ch-1] = s[count-1]
move.l %d5, %d6 | %d6 = pos = phase >> 16
lsr.l %d7, %d6 |
cmp.l %d2, %d6 | past end of samples?
bge.b 40f | skip resample loop| yes? skip loop
tst.l %d6 | need last sample of prev. frame?
bne.b 20f | resample loop | no? start main loop
move.l (%a3, %d6.l*4), %d1 | %d1 = s[pos]
bra.b 30f | resample start last | start with last (last in %d0)
20: | resample loop |
lea.l -4(%a3, %d6.l*4), %a5 | load s[pos-1] and s[pos]
movem.l (%a5), %d0-%d1 |
30: | resample start last |
sub.l %d0, %d1 | %d1 = diff = s[pos] - s[pos-1]
move.l %d0, %acc0 | %acc0 = previous sample
move.l %d5, %d0 | frac = (phase << 16) >> 1
lsl.l %d7, %d0 |
lsr.l #1, %d0 |
mac.l %d0, %d1, %acc0 | %acc0 += frac * diff
add.l %d4, %d5 | phase += delta
move.l %d5, %d6 | pos = phase >> 16
lsr.l %d7, %d6 |
movclr.l %acc0, %d0 |
move.l %d0, (%a4)+ | *d++ = %d0
cmp.l %d2, %d6 | pos < count?
blt.b 20b | resample loop | yes? continue resampling
40: | skip resample loop |
subq.l #1, %d3 | ch > 0?
bgt.b 10b | channel loop | yes? process next channel
lsl.l %d7, %d2 | wrap phase to start of next frame
sub.l %d2, %d5 | data->resample_data.phase =
move.l %d5, 12(%a0) | ... phase - (count << 16)
move.l %a4, %d0 | return d - d[0]
sub.l (%a2), %d0 |
asr.l #2, %d0 | convert bytes->samples
movem.l (%sp), %d2-%d7/%a2-%a5 | restore non-clobberables
lea.l 40(%sp), %sp | cleanup stack
rts | buh-bye
.size dsp_downsample,.-dsp_downsample
/****************************************************************************
* int dsp_upsample(int count, struct dsp_data *dsp,
* int32_t *src[], int32_t *dst[])
*/
.section .text
.align 2
.global dsp_upsample
dsp_upsample:
lea.l -40(%sp), %sp | save non-clobberables
movem.l %d2-%d7/%a2-%a5, (%sp) |
movem.l 44(%sp), %d2/%a0-%a2 | %d2 = count
| %a0 = data
| %a1 = src
| %a2 = dst
movem.l 4(%a0), %d3-%d4 | %d3 = ch = channels
| %d4 = delta = data->resample_data.delta
swap %d4 | swap delta to high word to use...
| ...carries to increment position
10: | channel loop |
move.l 12(%a0), %d5 | %d5 = phase = data->resample_data.phase
move.l -4(%a1, %d3.l*4), %a3 | %a3 = s = src[ch-1]
lea.l 12(%a0, %d3.l*4), %a4 | %a4 = &data->resample_data.last_sample[ch-1]
lea.l -4(%a3, %d2.l*4), %a5 | %a5 = src_end = &src[count-1]
move.l (%a4), %d0 | %d0 = last = data->resample_data.last_sample[ch-1]
move.l (%a5), (%a4) | data->resample_data.last_sample[ch-1] = s[count-1]
move.l -4(%a2, %d3.l*4), %a4 | %a4 = d = dst[ch-1]
move.l (%a3)+, %d1 | fetch first sample - might throw this...
| ...away later but we'll be preincremented
move.l %d1, %d6 | save sample value
sub.l %d0, %d1 | %d1 = diff = s[0] - last
swap %d5 | swap phase to high word to use
| carries to increment position
move.l %d5, %d7 | %d7 = pos = phase >> 16
clr.w %d5 |
eor.l %d5, %d7 | pos == 0?
beq.b 40f | loop start | yes? start loop
cmp.l %d2, %d7 | past end of samples?
bge.b 50f | skip resample loop| yes? go to next channel and collect info
lea.l (%a3, %d7.l*4), %a3 | %a3 = s = &s[pos+1]
movem.l -8(%a3), %d0-%d1 | %d0 = s[pos-1], %d1 = s[pos]
move.l %d1, %d6 | save sample value
sub.l %d0, %d1 | %d1 = diff = s[pos] - s[pos-1]
bra.b 40f | loop start |
20: | next sample loop |
move.l %d6, %d0 | move previous sample to %d0
move.l (%a3)+, %d1 | fetch next sample
move.l %d1, %d6 | save sample value
sub.l %d0, %d1 | %d1 = diff = s[pos] - s[pos-1]
30: | same sample loop |
movclr.l %acc0, %d7 | %d7 = result
move.l %d7, (%a4)+ | *d++ = %d7
40: | loop start |
lsr.l #1, %d5 | make phase into frac
move.l %d0, %acc0 | %acc0 = s[pos-1]
mac.l %d1, %d5, %acc0 | %acc0 = diff * frac
lsl.l #1, %d5 | restore frac to phase
add.l %d4, %d5 | phase += delta
bcc.b 30b | same sample loop | load next values?
cmp.l %a5, %a3 | src <= src_end?
bls.b 20b | next sample loop | yes? continue resampling
movclr.l %acc0, %d7 | %d7 = result
move.l %d7, (%a4)+ | *d++ = %d7
50: | skip resample loop |
subq.l #1, %d3 | ch > 0?
bgt.b 10b | channel loop | yes? process next channel
swap %d5 | wrap phase to start of next frame
move.l %d5, 12(%a0) | ...and save in data->resample_data.phase
move.l %a4, %d0 | return d - d[0]
sub.l (%a2), %d0 |
movem.l (%sp), %d2-%d7/%a2-%a5 | restore non-clobberables
asr.l #2, %d0 | convert bytes->samples
lea.l 40(%sp), %sp | cleanup stack
rts | buh-bye
.size dsp_upsample,.-dsp_upsample
/****************************************************************************
* void channels_process_sound_chan_mono(int count, int32_t *buf[])
*
* Mix left and right channels 50/50 into a center channel.
*/
.section .text
.align 2
.global channels_process_sound_chan_mono
channels_process_sound_chan_mono:
movem.l 4(%sp), %d0/%a0 | %d0 = count, %a0 = buf
lea.l -20(%sp), %sp | save registers
movem.l %d2-%d4/%a2-%a3, (%sp) |
movem.l (%a0), %a0-%a1 | get channel pointers
move.l %a0, %a2 | use separate dst pointers since read
move.l %a1, %a3 | pointers run one ahead of write
move.l #0x40000000, %d3 | %d3 = 0.5
move.l (%a0)+, %d1 | prime the input registers
move.l (%a1)+, %d2 |
mac.l %d1, %d3, (%a0)+, %d1, %acc0 |
mac.l %d2, %d3, (%a1)+, %d2, %acc0 |
subq.l #1, %d0 |
ble.s 20f | loop done |
10: | loop |
movclr.l %acc0, %d4 | L = R = l/2 + r/2
mac.l %d1, %d3, (%a0)+, %d1, %acc0 |
mac.l %d2, %d3, (%a1)+, %d2, %acc0 |
move.l %d4, (%a2)+ | output to original buffer
move.l %d4, (%a3)+ |
subq.l #1, %d0 |
bgt.s 10b | loop |
20: | loop done |
movclr.l %acc0, %d4 | output last sample
move.l %d4, (%a2) |
move.l %d4, (%a3) |
movem.l (%sp), %d2-%d4/%a2-%a3 | restore registers
lea.l 20(%sp), %sp | cleanup
rts |
.size channels_process_sound_chan_mono, \
.-channels_process_sound_chan_mono
/****************************************************************************
* void channels_process_sound_chan_custom(int count, int32_t *buf[])
*
* Apply stereo width (narrowing/expanding) effect.
*/
.section .text
.align 2
.global channels_process_sound_chan_custom
channels_process_sound_chan_custom:
movem.l 4(%sp), %d0/%a0 | %d0 = count, %a0 = buf
lea.l -28(%sp), %sp | save registers
movem.l %d2-%d6/%a2-%a3, (%sp) |
movem.l (%a0), %a0-%a1 | get channel pointers
move.l %a0, %a2 | use separate dst pointers since read
move.l %a1, %a3 | pointers run one ahead of write
move.l dsp_sw_gain, %d3 | load straight (mid) gain
move.l dsp_sw_cross, %d4 | load cross (side) gain
move.l (%a0)+, %d1 | prime the input registers
move.l (%a1)+, %d2 |
mac.l %d1, %d3 , %acc0 | L = l*gain + r*cross
mac.l %d1, %d4, (%a0)+, %d1, %acc1 | R = r*gain + l*cross
mac.l %d2, %d4 , %acc0 |
mac.l %d2, %d3, (%a1)+, %d2, %acc1 |
subq.l #1, %d0 |
ble.b 20f | loop done |
10: | loop |
movclr.l %acc0, %d5 |
movclr.l %acc1, %d6 |
mac.l %d1, %d3 , %acc0 | L = l*gain + r*cross
mac.l %d1, %d4, (%a0)+, %d1, %acc1 | R = r*gain + l*cross
mac.l %d2, %d4 , %acc0 |
mac.l %d2, %d3, (%a1)+, %d2, %acc1 |
move.l %d5, (%a2)+ |
move.l %d6, (%a3)+ |
subq.l #1, %d0 |
bgt.s 10b | loop |
20: | loop done |
movclr.l %acc0, %d5 | output last sample
movclr.l %acc1, %d6 |
move.l %d5, (%a2) |
move.l %d6, (%a3) |
movem.l (%sp), %d2-%d6/%a2-%a3 | restore registers
lea.l 28(%sp), %sp | cleanup
rts |
.size channels_process_sound_chan_custom, \
.-channels_process_sound_chan_custom
/****************************************************************************
* void channels_process_sound_chan_karaoke(int count, int32_t *buf[])
*
* Separate channels into side channels.
*/
.section .text
.align 2
.global channels_process_sound_chan_karaoke
channels_process_sound_chan_karaoke:
movem.l 4(%sp), %d0/%a0 | %d0 = count, %a0 = buf
lea.l -20(%sp), %sp | save registers
movem.l %d2-%d4/%a2-%a3, (%sp) |
movem.l (%a0), %a0-%a1 | get channel src pointers
move.l %a0, %a2 | use separate dst pointers since read
move.l %a1, %a3 | pointers run one ahead of write
move.l #0x40000000, %d3 | %d3 = 0.5
move.l (%a0)+, %d1 | prime the input registers
move.l (%a1)+, %d2 |
mac.l %d1, %d3, (%a0)+, %d1, %acc0 | L = l/2 - r/2
msac.l %d2, %d3, (%a1)+, %d2, %acc0 |
subq.l #1, %d0 |
ble.b 20f | loop done |
10: | loop |
movclr.l %acc0, %d4 |
mac.l %d1, %d3, (%a0)+, %d1, %acc0 | L = l/2 - r/2
msac.l %d2, %d3, (%a1)+, %d2, %acc0 |
move.l %d4, (%a2)+ |
neg.l %d4 | R = -L = -(l/2 - r/2) = r/2 - l/2
move.l %d4, (%a3)+ |
subq.l #1, %d0 |
bgt.s 10b | loop |
20: | loop done |
movclr.l %acc0, %d4 | output last sample
move.l %d4, (%a2) |
neg.l %d4 | R = -L = -(l/2 - r/2) = r/2 - l/2
move.l %d4, (%a3) |
movem.l (%sp), %d2-%d4/%a2-%a3 | restore registers
lea.l 20(%sp), %sp | cleanup
rts |
.size channels_process_sound_chan_karaoke, \
.-channels_process_sound_chan_karaoke
/****************************************************************************
* void sample_output_stereo(int count, struct dsp_data *data,
* int32_t *src[], int16_t *dst)
*
* Framework based on the ubiquitous Rockbox line transfer logic for
* Coldfire CPUs.
*
* Does emac clamping and scaling (which proved faster than the usual
* checks and branches - even single test clamping) and writes using
* line burst transfers. Also better than writing a single L-R pair per
* loop but a good deal more code.
*
* Attemping bursting during reads is rather futile since the source and
* destination alignments rarely agree and too much complication will
* slow us up. The parallel loads seem to do a bit better at least until
* a pcm buffer can always give line aligned chunk and then aligning the
* dest can then imply the source is aligned if the source buffers are.
* For now longword alignment is assumed of both the source and dest.
*
*/
.section .text
.align 2
.global sample_output_stereo
sample_output_stereo:
lea.l -48(%sp), %sp | save registers
move.l %macsr, %d1 | do it now as at many lines will
movem.l %d1-%d7/%a2-%a6, (%sp) | be the far more common condition
move.l #0x80, %macsr | put emac unit in signed int mode
movem.l 52(%sp), %a0-%a2/%a4 |
lea.l (%a4, %a0.l*4), %a0 | %a0 = end address
move.l (%a1), %d1 | %a1 = multiplier: (1 << (16 - scale))
sub.l #16, %d1 |
neg.l %d1 |
moveq.l #1, %d0 |
asl.l %d1, %d0 |
move.l %d0, %a1 |
move.l #0x8000, %a6 | %a6 = rounding term
movem.l (%a2), %a2-%a3 | get L/R channel pointers
moveq.l #28, %d0 | %d0 = second line bound
add.l %a4, %d0 |
and.l #0xfffffff0, %d0 |
cmp.l %a0, %d0 | at least a full line?
bhi.w 40f | long loop 1 start | no? do as trailing longwords
sub.l #16, %d0 | %d1 = first line bound
cmp.l %a4, %d0 | any leading longwords?
bls.b 20f | line loop start | no? start line loop
10: | long loop 0 |
move.l (%a2)+, %d1 | read longword from L and R
move.l %a6, %acc0 |
move.l %acc0, %acc1 |
mac.l %d1, %a1, (%a3)+, %d2, %acc0 | shift L to high word
mac.l %d2, %a1, %acc1 | shift R to high word
movclr.l %acc0, %d1 | get possibly saturated results
movclr.l %acc1, %d2 |
swap %d2 | move R to low word
move.w %d2, %d1 | interleave MS 16 bits of each
move.l %d1, (%a4)+ | ...and write both
cmp.l %a4, %d0 |
bhi.b 10b | long loop 0 |
20: | line loop start |
lea.l -12(%a0), %a5 | %a5 = at or just before last line bound
30: | line loop |
move.l (%a3)+, %d4 | get next 4 R samples and scale
move.l %a6, %acc0 |
move.l %acc0, %acc1 |
move.l %acc1, %acc2 |
move.l %acc2, %acc3 |
mac.l %d4, %a1, (%a3)+, %d5, %acc0 | with saturation
mac.l %d5, %a1, (%a3)+, %d6, %acc1 |
mac.l %d6, %a1, (%a3)+, %d7, %acc2 |
mac.l %d7, %a1, (%a2)+, %d0, %acc3 |
lea.l 16(%a4), %a4 | increment dest here, mitigate stalls
movclr.l %acc0, %d4 | obtain R results
movclr.l %acc1, %d5 |
movclr.l %acc2, %d6 |
movclr.l %acc3, %d7 |
move.l %a6, %acc0 |
move.l %acc0, %acc1 |
move.l %acc1, %acc2 |
move.l %acc2, %acc3 |
mac.l %d0, %a1, (%a2)+, %d1, %acc0 | get next 4 L samples and scale
mac.l %d1, %a1, (%a2)+, %d2, %acc1 | with saturation
mac.l %d2, %a1, (%a2)+, %d3, %acc2 |
mac.l %d3, %a1 , %acc3 |
swap %d4 | a) interleave most significant...
swap %d5 |
swap %d6 |
swap %d7 |
movclr.l %acc0, %d0 | obtain L results
movclr.l %acc1, %d1 |
movclr.l %acc2, %d2 |
movclr.l %acc3, %d3 |
move.w %d4, %d0 | a) ... 16 bits of L and R
move.w %d5, %d1 |
move.w %d6, %d2 |
move.w %d7, %d3 |
movem.l %d0-%d3, -16(%a4) | write four stereo samples
cmp.l %a4, %a5 |
bhi.b 30b | line loop |
40: | long loop 1 start |
cmp.l %a4, %a0 | any longwords left?
bls.b 60f | output end | no? stop
50: | long loop 1 |
move.l (%a2)+, %d1 | handle trailing longwords
move.l %a6, %acc0 |
move.l %acc0, %acc1 |
mac.l %d1, %a1, (%a3)+, %d2, %acc0 | the same way as leading ones
mac.l %d2, %a1, %acc1 |
movclr.l %acc0, %d1 |
movclr.l %acc1, %d2 |
swap %d2 |
move.w %d2, %d1 |
move.l %d1, (%a4)+ |
cmp.l %a4, %a0 |
bhi.b 50b | long loop 1
60: | output end |
movem.l (%sp), %d1-%d7/%a2-%a6 | restore registers
move.l %d1, %macsr |
lea.l 48(%sp), %sp | cleanup
rts |
.size sample_output_stereo, .-sample_output_stereo
/****************************************************************************
* void sample_output_mono(int count, struct dsp_data *data,
* int32_t *src[], int16_t *dst)
*
* Same treatment as sample_output_stereo but for one channel.
*/
.section .text
.align 2
.global sample_output_mono
sample_output_mono:
lea.l -32(%sp), %sp | save registers
move.l %macsr, %d1 | do it now as at many lines will
movem.l %d1-%d5/%a2-%a4, (%sp) | be the far more common condition
move.l #0x80, %macsr | put emac unit in signed int mode
movem.l 36(%sp), %a0-%a3 |
lea.l (%a3, %a0.l*4), %a0 | %a0 = end address
move.l (%a1), %d1 | %d5 = multiplier: (1 << (16 - scale))
sub.l #16, %d1 |
neg.l %d1 |
moveq.l #1, %d5 |
asl.l %d1, %d5 |
move.l #0x8000, %a4 | %a4 = rounding term
movem.l (%a2), %a2 | get source channel pointer
moveq.l #28, %d0 | %d0 = second line bound
add.l %a3, %d0 |
and.l #0xfffffff0, %d0 |
cmp.l %a0, %d0 | at least a full line?
bhi.w 40f | long loop 1 start | no? do as trailing longwords
sub.l #16, %d0 | %d1 = first line bound
cmp.l %a3, %d0 | any leading longwords?
bls.b 20f | line loop start | no? start line loop
10: | long loop 0 |
move.l (%a2)+, %d1 | read longword from L and R
move.l %a4, %acc0 |
mac.l %d1, %d5, %acc0 | shift L to high word
movclr.l %acc0, %d1 | get possibly saturated results
move.l %d1, %d2 |
swap %d2 | move R to low word
move.w %d2, %d1 | duplicate single channel into
move.l %d1, (%a3)+ | L and R
cmp.l %a3, %d0 |
bhi.b 10b | long loop 0 |
20: | line loop start |
lea.l -12(%a0), %a1 | %a1 = at or just before last line bound
30: | line loop |
move.l (%a2)+, %d0 | get next 4 L samples and scale
move.l %a4, %acc0 |
move.l %acc0, %acc1 |
move.l %acc1, %acc2 |
move.l %acc2, %acc3 |
mac.l %d0, %d5, (%a2)+, %d1, %acc0 | with saturation
mac.l %d1, %d5, (%a2)+, %d2, %acc1 |
mac.l %d2, %d5, (%a2)+, %d3, %acc2 |
mac.l %d3, %d5 , %acc3 |
lea.l 16(%a3), %a3 | increment dest here, mitigate stalls
movclr.l %acc0, %d0 | obtain results
movclr.l %acc1, %d1 |
movclr.l %acc2, %d2 |
movclr.l %acc3, %d3 |
move.l %d0, %d4 | duplicate single channel
swap %d4 | into L and R
move.w %d4, %d0 |
move.l %d1, %d4 |
swap %d4 |
move.w %d4, %d1 |
move.l %d2, %d4 |
swap %d4 |
move.w %d4, %d2 |
move.l %d3, %d4 |
swap %d4 |
move.w %d4, %d3 |
movem.l %d0-%d3, -16(%a3) | write four stereo samples
cmp.l %a3, %a1 |
bhi.b 30b | line loop |
40: | long loop 1 start |
cmp.l %a3, %a0 | any longwords left?
bls.b 60f | output end | no? stop
50: | loop loop 1 |
move.l (%a2)+, %d1 | handle trailing longwords
move.l %a4, %acc0 |
mac.l %d1, %d5, %acc0 | the same way as leading ones
movclr.l %acc0, %d1 |
move.l %d1, %d2 |
swap %d2 |
move.w %d2, %d1 |
move.l %d1, (%a3)+ |
cmp.l %a3, %a0 |
bhi.b 50b | long loop 1 |
60: | output end |
movem.l (%sp), %d1-%d5/%a2-%a4 | restore registers
move.l %d1, %macsr |
lea.l 32(%sp), %sp | cleanup
rts |
.size sample_output_mono, .-sample_output_mono
|
