xref: /dragonfly/sys/dev/sound/pcm/feeder_rate.c (revision ec3c426ee654c335a79c718fe487b9168dda87f7)
1 /*-
2  * Copyright (c) 2005-2009 Ariff Abdullah <ariff@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 /*
28  * feeder_rate: (Codename: Z Resampler), which means any effort to create
29  *              future replacement for this resampler are simply absurd unless
30  *              the world decide to add new alphabet after Z.
31  *
32  * FreeBSD bandlimited sinc interpolator, technically based on
33  * "Digital Audio Resampling" by Julius O. Smith III
34  *  - http://ccrma.stanford.edu/~jos/resample/
35  *
36  * The Good:
37  * + all out fixed point integer operations, no soft-float or anything like
38  *   that.
39  * + classic polyphase converters with high quality coefficient's polynomial
40  *   interpolators.
41  * + fast, faster, or the fastest of its kind.
42  * + compile time configurable.
43  * + etc etc..
44  *
45  * The Bad:
46  * - The z, z_, and Z_ . Due to mental block (or maybe just 0x7a69), I
47  *   couldn't think of anything simpler than that (feeder_rate_xxx is just
48  *   too long). Expect possible clashes with other zitizens (any?).
49  */
50 
51 #ifdef _KERNEL
52 #ifdef HAVE_KERNEL_OPTION_HEADERS
53 #include "opt_snd.h"
54 #endif
55 #include <dev/sound/pcm/sound.h>
56 #include <dev/sound/pcm/pcm.h>
57 #include "feeder_if.h"
58 
59 #define SND_USE_FXDIV
60 #include "snd_fxdiv_gen.h"
61 
62 SND_DECLARE_FILE("$FreeBSD: head/sys/dev/sound/pcm/feeder_rate.c 267992 2014-06-28 03:56:17Z hselasky $");
63 #endif
64 
65 #include "feeder_rate_gen.h"
66 
67 #if !defined(_KERNEL) && defined(SND_DIAGNOSTIC)
68 #undef Z_DIAGNOSTIC
69 #define Z_DIAGNOSTIC                    1
70 #elif defined(_KERNEL)
71 #undef Z_DIAGNOSTIC
72 #endif
73 
74 #ifndef Z_QUALITY_DEFAULT
75 #define Z_QUALITY_DEFAULT     Z_QUALITY_LINEAR
76 #endif
77 
78 #define Z_RESERVOIR           2048
79 #define Z_RESERVOIR_MAX                 131072
80 
81 #define Z_SINC_MAX            0x3fffff
82 #define Z_SINC_DOWNMAX                  48                  /* 384000 / 8000 */
83 
84 #ifdef _KERNEL
85 #define Z_POLYPHASE_MAX                 183040              /* 286 taps, 640 phases */
86 #else
87 #define Z_POLYPHASE_MAX                 1464320             /* 286 taps, 5120 phases */
88 #endif
89 
90 #define Z_RATE_DEFAULT                  48000
91 
92 #define Z_RATE_MIN            FEEDRATE_RATEMIN
93 #define Z_RATE_MAX            FEEDRATE_RATEMAX
94 #define Z_ROUNDHZ             FEEDRATE_ROUNDHZ
95 #define Z_ROUNDHZ_MIN                   FEEDRATE_ROUNDHZ_MIN
96 #define Z_ROUNDHZ_MAX                   FEEDRATE_ROUNDHZ_MAX
97 
98 #define Z_RATE_SRC            FEEDRATE_SRC
99 #define Z_RATE_DST            FEEDRATE_DST
100 #define Z_RATE_QUALITY                  FEEDRATE_QUALITY
101 #define Z_RATE_CHANNELS                 FEEDRATE_CHANNELS
102 
103 #define Z_PARANOID            1
104 
105 #define Z_MULTIFORMAT                   1
106 
107 #ifdef _KERNEL
108 #undef Z_USE_ALPHADRIFT
109 #define Z_USE_ALPHADRIFT      1
110 #endif
111 
112 #define Z_FACTOR_MIN                    1
113 #define Z_FACTOR_MAX                    Z_MASK
114 #define Z_FACTOR_SAFE(v)      (!((v) < Z_FACTOR_MIN || (v) > Z_FACTOR_MAX))
115 
116 struct z_info;
117 
118 typedef void (*z_resampler_t)(struct z_info *, uint8_t *);
119 
120 struct z_info {
121           int32_t rsrc, rdst; /* original source / destination rates */
122           int32_t src, dst;   /* rounded source / destination rates */
123           int32_t channels;   /* total channels */
124           int32_t bps;                  /* bytes-per-sample */
125           int32_t quality;    /* resampling quality */
126 
127           int32_t z_gx, z_gy; /* interpolation / decimation ratio */
128           int32_t z_alpha;    /* output sample time phase / drift */
129           uint8_t *z_delay;   /* FIR delay line / linear buffer */
130           int32_t *z_coeff;   /* FIR coefficients */
131           int32_t *z_dcoeff;  /* FIR coefficients differences */
132           int32_t *z_pcoeff;  /* FIR polyphase coefficients */
133           int32_t z_scale;    /* output scaling */
134           int32_t z_dx;                 /* input sample drift increment */
135           int32_t z_dy;                 /* output sample drift increment */
136 #ifdef Z_USE_ALPHADRIFT
137           int32_t z_alphadrift;         /* alpha drift rate */
138           int32_t z_startdrift;         /* buffer start position drift rate */
139 #endif
140           int32_t z_mask;               /* delay line full length mask */
141           int32_t z_size;               /* half width of FIR taps */
142           int32_t z_full;               /* full size of delay line */
143           int32_t z_alloc;    /* largest allocated full size of delay line */
144           int32_t z_start;    /* buffer processing start position */
145           int32_t z_pos;                /* current position for the next feed */
146 #ifdef Z_DIAGNOSTIC
147           uint32_t z_cycle;   /* output cycle, purely for statistical */
148 #endif
149           int32_t z_maxfeed;  /* maximum feed to avoid 32bit overflow */
150 
151           z_resampler_t z_resample;
152 };
153 
154 int feeder_rate_min = Z_RATE_MIN;
155 int feeder_rate_max = Z_RATE_MAX;
156 int feeder_rate_round = Z_ROUNDHZ;
157 int feeder_rate_quality = Z_QUALITY_DEFAULT;
158 
159 static int feeder_rate_polyphase_max = Z_POLYPHASE_MAX;
160 
161 #ifdef _KERNEL
162 static char feeder_rate_presets[] = FEEDER_RATE_PRESETS;
163 SYSCTL_STRING(_hw_snd, OID_AUTO, feeder_rate_presets, CTLFLAG_RD,
164     &feeder_rate_presets, 0, "compile-time rate presets");
165 
166 TUNABLE_INT("hw.snd.feeder_rate_min", &feeder_rate_min);
167 TUNABLE_INT("hw.snd.feeder_rate_max", &feeder_rate_max);
168 TUNABLE_INT("hw.snd.feeder_rate_round", &feeder_rate_round);
169 TUNABLE_INT("hw.snd.feeder_rate_quality", &feeder_rate_quality);
170 
171 TUNABLE_INT("hw.snd.feeder_rate_polyphase_max", &feeder_rate_polyphase_max);
172 SYSCTL_INT(_hw_snd, OID_AUTO, feeder_rate_polyphase_max, CTLFLAG_RW,
173     &feeder_rate_polyphase_max, 0, "maximum allowable polyphase entries");
174 
175 static int
sysctl_hw_snd_feeder_rate_min(SYSCTL_HANDLER_ARGS)176 sysctl_hw_snd_feeder_rate_min(SYSCTL_HANDLER_ARGS)
177 {
178           int err, val;
179 
180           val = feeder_rate_min;
181           err = sysctl_handle_int(oidp, &val, 0, req);
182 
183           if (err != 0 || req->newptr == NULL || val == feeder_rate_min)
184                     return (err);
185 
186           if (!(Z_FACTOR_SAFE(val) && val < feeder_rate_max))
187                     return (EINVAL);
188 
189           feeder_rate_min = val;
190 
191           return (0);
192 }
193 SYSCTL_PROC(_hw_snd, OID_AUTO, feeder_rate_min, CTLTYPE_INT | CTLFLAG_RW,
194     0, sizeof(int), sysctl_hw_snd_feeder_rate_min, "I",
195     "minimum allowable rate");
196 
197 static int
sysctl_hw_snd_feeder_rate_max(SYSCTL_HANDLER_ARGS)198 sysctl_hw_snd_feeder_rate_max(SYSCTL_HANDLER_ARGS)
199 {
200           int err, val;
201 
202           val = feeder_rate_max;
203           err = sysctl_handle_int(oidp, &val, 0, req);
204 
205           if (err != 0 || req->newptr == NULL || val == feeder_rate_max)
206                     return (err);
207 
208           if (!(Z_FACTOR_SAFE(val) && val > feeder_rate_min))
209                     return (EINVAL);
210 
211           feeder_rate_max = val;
212 
213           return (0);
214 }
215 SYSCTL_PROC(_hw_snd, OID_AUTO, feeder_rate_max, CTLTYPE_INT | CTLFLAG_RW,
216     0, sizeof(int), sysctl_hw_snd_feeder_rate_max, "I",
217     "maximum allowable rate");
218 
219 static int
sysctl_hw_snd_feeder_rate_round(SYSCTL_HANDLER_ARGS)220 sysctl_hw_snd_feeder_rate_round(SYSCTL_HANDLER_ARGS)
221 {
222           int err, val;
223 
224           val = feeder_rate_round;
225           err = sysctl_handle_int(oidp, &val, 0, req);
226 
227           if (err != 0 || req->newptr == NULL || val == feeder_rate_round)
228                     return (err);
229 
230           if (val < Z_ROUNDHZ_MIN || val > Z_ROUNDHZ_MAX)
231                     return (EINVAL);
232 
233           feeder_rate_round = val - (val % Z_ROUNDHZ);
234 
235           return (0);
236 }
237 SYSCTL_PROC(_hw_snd, OID_AUTO, feeder_rate_round, CTLTYPE_INT | CTLFLAG_RW,
238     0, sizeof(int), sysctl_hw_snd_feeder_rate_round, "I",
239     "sample rate converter rounding threshold");
240 
241 static int
sysctl_hw_snd_feeder_rate_quality(SYSCTL_HANDLER_ARGS)242 sysctl_hw_snd_feeder_rate_quality(SYSCTL_HANDLER_ARGS)
243 {
244           struct snddev_info *d;
245           struct pcm_channel *c;
246           struct pcm_feeder *f;
247           int i, err, val;
248 
249           val = feeder_rate_quality;
250           err = sysctl_handle_int(oidp, &val, 0, req);
251 
252           if (err != 0 || req->newptr == NULL || val == feeder_rate_quality)
253                     return (err);
254 
255           if (val < Z_QUALITY_MIN || val > Z_QUALITY_MAX)
256                     return (EINVAL);
257 
258           feeder_rate_quality = val;
259 
260           /*
261            * Traverse all available channels on each device and try to
262            * set resampler quality if and only if it is exist as
263            * part of feeder chains and the channel is idle.
264            */
265           for (i = 0; pcm_devclass != NULL &&
266               i < devclass_get_maxunit(pcm_devclass); i++) {
267                     d = devclass_get_softc(pcm_devclass, i);
268                     if (!PCM_REGISTERED(d))
269                               continue;
270                     PCM_LOCK(d);
271                     PCM_WAIT(d);
272                     PCM_ACQUIRE(d);
273                     CHN_FOREACH(c, d, channels.pcm) {
274                               CHN_LOCK(c);
275                               f = chn_findfeeder(c, FEEDER_RATE);
276                               if (f == NULL || f->data == NULL || CHN_STARTED(c)) {
277                                         CHN_UNLOCK(c);
278                                         continue;
279                               }
280                               (void)FEEDER_SET(f, FEEDRATE_QUALITY, val);
281                               CHN_UNLOCK(c);
282                     }
283                     PCM_RELEASE(d);
284                     PCM_UNLOCK(d);
285           }
286 
287           return (0);
288 }
289 SYSCTL_PROC(_hw_snd, OID_AUTO, feeder_rate_quality, CTLTYPE_INT | CTLFLAG_RW,
290     0, sizeof(int), sysctl_hw_snd_feeder_rate_quality, "I",
291     "sample rate converter quality ("__XSTRING(Z_QUALITY_MIN)"=low .. "
292     __XSTRING(Z_QUALITY_MAX)"=high)");
293 #endif    /* _KERNEL */
294 
295 
296 /*
297  * Resampler type.
298  */
299 #define Z_IS_ZOH(i)           ((i)->quality == Z_QUALITY_ZOH)
300 #define Z_IS_LINEAR(i)                  ((i)->quality == Z_QUALITY_LINEAR)
301 #define Z_IS_SINC(i)                    ((i)->quality > Z_QUALITY_LINEAR)
302 
303 /*
304  * Macroses for accurate sample time drift calculations.
305  *
306  * gy2gx : given the amount of output, return the _exact_ required amount of
307  *         input.
308  * gx2gy : given the amount of input, return the _maximum_ amount of output
309  *         that will be generated.
310  * drift : given the amount of input and output, return the elapsed
311  *         sample-time.
312  */
313 #define _Z_GCAST(x)           ((uint64_t)(x))
314 
315 #ifdef __x86_64__
316 #define Z_DIV(x, y)           ((x) / (y))
317 #endif
318 
319 #define _Z_GY2GX(i, a, v)                                                       \
320           Z_DIV(((_Z_GCAST((i)->z_gx) * (v)) + ((i)->z_gy - (a) - 1)),          \
321           (i)->z_gy)
322 
323 #define _Z_GX2GY(i, a, v)                                                       \
324           Z_DIV(((_Z_GCAST((i)->z_gy) * (v)) + (a)), (i)->z_gx)
325 
326 #define _Z_DRIFT(i, x, y)                                                       \
327           ((_Z_GCAST((i)->z_gy) * (x)) - (_Z_GCAST((i)->z_gx) * (y)))
328 
329 #define z_gy2gx(i, v)                   _Z_GY2GX(i, (i)->z_alpha, v)
330 #define z_gx2gy(i, v)                   _Z_GX2GY(i, (i)->z_alpha, v)
331 #define z_drift(i, x, y)      _Z_DRIFT(i, x, y)
332 
333 /*
334  * Macroses for SINC coefficients table manipulations.. whatever.
335  */
336 #define Z_SINC_COEFF_IDX(i)   ((i)->quality - Z_QUALITY_LINEAR - 1)
337 
338 #define Z_SINC_LEN(i)                                                                     \
339           ((int32_t)(((uint64_t)z_coeff_tab[Z_SINC_COEFF_IDX(i)].len <<         \
340               Z_SHIFT) / (i)->z_dy))
341 
342 #define Z_SINC_BASE_LEN(i)                                                      \
343           ((z_coeff_tab[Z_SINC_COEFF_IDX(i)].len - 1) >> (Z_DRIFT_SHIFT - 1))
344 
345 /*
346  * Macroses for linear delay buffer operations. Alignment is not
347  * really necessary since we're not using true circular buffer, but it
348  * will help us guard against possible trespasser. To be honest,
349  * the linear block operations does not need guarding at all due to
350  * accurate drifting!
351  */
352 #define z_align(i, v)                   ((v) & (i)->z_mask)
353 #define z_next(i, o, v)                 z_align(i, (o) + (v))
354 #define z_prev(i, o, v)                 z_align(i, (o) - (v))
355 #define z_fetched(i)                    (z_align(i, (i)->z_pos - (i)->z_start) - 1)
356 #define z_free(i)             ((i)->z_full - (i)->z_pos)
357 
358 /*
359  * Macroses for Bla Bla .. :)
360  */
361 #define z_copy(src, dst, sz)  (void)memcpy(dst, src, sz)
362 #define z_feed(...)           FEEDER_FEED(__VA_ARGS__)
363 
364 static __inline uint32_t
z_min(uint32_t x,uint32_t y)365 z_min(uint32_t x, uint32_t y)
366 {
367 
368           return ((x < y) ? x : y);
369 }
370 
371 static int32_t
z_gcd(int32_t x,int32_t y)372 z_gcd(int32_t x, int32_t y)
373 {
374           int32_t w;
375 
376           while (y != 0) {
377                     w = x % y;
378                     x = y;
379                     y = w;
380           }
381 
382           return (x);
383 }
384 
385 static int32_t
z_roundpow2(int32_t v)386 z_roundpow2(int32_t v)
387 {
388           int32_t i;
389 
390           i = 1;
391 
392           /*
393            * Let it overflow at will..
394            */
395           while (i > 0 && i < v)
396                     i <<= 1;
397 
398           return (i);
399 }
400 
401 /*
402  * Zero Order Hold, the worst of the worst, an insult against quality,
403  * but super fast.
404  */
405 static void
z_feed_zoh(struct z_info * info,uint8_t * dst)406 z_feed_zoh(struct z_info *info, uint8_t *dst)
407 {
408 #if 0
409           z_copy(info->z_delay +
410               (info->z_start * info->channels * info->bps), dst,
411               info->channels * info->bps);
412 #else
413           uint32_t cnt;
414           uint8_t *src;
415 
416           cnt = info->channels * info->bps;
417           src = info->z_delay + (info->z_start * cnt);
418 
419           /*
420            * This is a bit faster than doing bcopy() since we're dealing
421            * with possible unaligned samples.
422            */
423           do {
424                     *dst++ = *src++;
425           } while (--cnt != 0);
426 #endif
427 }
428 
429 /*
430  * Linear Interpolation. This at least sounds better (perceptually) and fast,
431  * but without any proper filtering which means aliasing still exist and
432  * could become worst with a right sample. Interpolation centered within
433  * Z_LINEAR_ONE between the present and previous sample and everything is
434  * done with simple 32bit scaling arithmetic.
435  */
436 #define Z_DECLARE_LINEAR(SIGN, BIT, ENDIAN)                                               \
437 static void                                                                                         \
438 z_feed_linear_##SIGN##BIT##ENDIAN(struct z_info *info, uint8_t *dst)            \
439 {                                                                                                   \
440           int32_t z;                                                                                \
441           intpcm_t x, y;                                                                            \
442           uint32_t ch;                                                                              \
443           uint8_t *sx, *sy;                                                               \
444                                                                                                     \
445           z = ((uint32_t)info->z_alpha * info->z_dx) >> Z_LINEAR_UNSHIFT;                 \
446                                                                                                     \
447           sx = info->z_delay + (info->z_start * info->channels *                          \
448               PCM_##BIT##_BPS);                                                                     \
449           sy = sx - (info->channels * PCM_##BIT##_BPS);                                   \
450                                                                                                     \
451           ch = info->channels;                                                                      \
452                                                                                                     \
453           do {                                                                                      \
454                     x = _PCM_READ_##SIGN##BIT##_##ENDIAN(sx);                             \
455                     y = _PCM_READ_##SIGN##BIT##_##ENDIAN(sy);                             \
456                     x = Z_LINEAR_INTERPOLATE_##BIT(z, x, y);                              \
457                     _PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst, x);                            \
458                     sx += PCM_##BIT##_BPS;                                                          \
459                     sy += PCM_##BIT##_BPS;                                                          \
460                     dst += PCM_##BIT##_BPS;                                                         \
461           } while (--ch != 0);                                                                      \
462 }
463 
464 /*
465  * Userland clipping diagnostic check, not enabled in kernel compilation.
466  * While doing sinc interpolation, unrealistic samples like full scale sine
467  * wav will clip, but for other things this will not make any noise at all.
468  * Everybody should learn how to normalized perceived loudness of their own
469  * music/sounds/samples (hint: ReplayGain).
470  */
471 #ifdef Z_DIAGNOSTIC
472 #define Z_CLIP_CHECK(v, BIT)  do {                                              \
473           if ((v) > PCM_S##BIT##_MAX) {                                         \
474                     fprintf(stderr, "Overflow: v=%jd, max=%jd\n",               \
475                         (intmax_t)(v), (intmax_t)PCM_S##BIT##_MAX);             \
476           } else if ((v) < PCM_S##BIT##_MIN) {                                  \
477                     fprintf(stderr, "Underflow: v=%jd, min=%jd\n",              \
478                         (intmax_t)(v), (intmax_t)PCM_S##BIT##_MIN);             \
479           }                                                                               \
480 } while (0)
481 #else
482 #define Z_CLIP_CHECK(...)
483 #endif
484 
485 #define Z_CLAMP(v, BIT)                                                                   \
486           (((v) > PCM_S##BIT##_MAX) ? PCM_S##BIT##_MAX :                        \
487           (((v) < PCM_S##BIT##_MIN) ? PCM_S##BIT##_MIN : (v)))
488 
489 /*
490  * Sine Cardinal (SINC) Interpolation. Scaling is done in 64 bit, so
491  * there's no point to hold the plate any longer. All samples will be
492  * shifted to a full 32 bit, scaled and restored during write for
493  * maximum dynamic range (only for downsampling).
494  */
495 #define _Z_SINC_ACCUMULATE(SIGN, BIT, ENDIAN, adv)                              \
496           c += z >> Z_SHIFT;                                                    \
497           z &= Z_MASK;                                                                    \
498           coeff = Z_COEFF_INTERPOLATE(z, z_coeff[c], z_dcoeff[c]);    \
499           x = _PCM_READ_##SIGN##BIT##_##ENDIAN(p);                              \
500           v += Z_NORM_##BIT((intpcm64_t)x * coeff);                             \
501           z += info->z_dy;                                                      \
502           p adv##= info->channels * PCM_##BIT##_BPS
503 
504 /*
505  * XXX GCC4 optimization is such a !@#$%, need manual unrolling.
506  */
507 #if defined(__GNUC__) && __GNUC__ >= 4
508 #define Z_SINC_ACCUMULATE(...)          do {                                              \
509           _Z_SINC_ACCUMULATE(__VA_ARGS__);                                      \
510           _Z_SINC_ACCUMULATE(__VA_ARGS__);                                      \
511 } while (0)
512 #define Z_SINC_ACCUMULATE_DECR                    2
513 #else
514 #define Z_SINC_ACCUMULATE(...)          do {                                              \
515           _Z_SINC_ACCUMULATE(__VA_ARGS__);                                      \
516 } while (0)
517 #define Z_SINC_ACCUMULATE_DECR                    1
518 #endif
519 
520 #define Z_DECLARE_SINC(SIGN, BIT, ENDIAN)                                                 \
521 static void                                                                                         \
522 z_feed_sinc_##SIGN##BIT##ENDIAN(struct z_info *info, uint8_t *dst)              \
523 {                                                                                                   \
524           intpcm64_t v;                                                                             \
525           intpcm_t x;                                                                               \
526           uint8_t *p;                                                                               \
527           int32_t coeff, z, *z_coeff, *z_dcoeff;                                          \
528           uint32_t c, center, ch, i;                                                      \
529                                                                                                     \
530           z_coeff = info->z_coeff;                                                        \
531           z_dcoeff = info->z_dcoeff;                                                      \
532           center = z_prev(info, info->z_start, info->z_size);                             \
533           ch = info->channels * PCM_##BIT##_BPS;                                          \
534           dst += ch;                                                                                \
535                                                                                                     \
536           do {                                                                                      \
537                     dst -= PCM_##BIT##_BPS;                                                         \
538                     ch -= PCM_##BIT##_BPS;                                                          \
539                     v = 0;                                                                          \
540                     z = info->z_alpha * info->z_dx;                                                 \
541                     c = 0;                                                                          \
542                     p = info->z_delay + (z_next(info, center, 1) *                        \
543                         info->channels * PCM_##BIT##_BPS) + ch;                           \
544                     for (i = info->z_size; i != 0; i -= Z_SINC_ACCUMULATE_DECR)           \
545                               Z_SINC_ACCUMULATE(SIGN, BIT, ENDIAN, +);                    \
546                     z = info->z_dy - (info->z_alpha * info->z_dx);                        \
547                     c = 0;                                                                          \
548                     p = info->z_delay + (center * info->channels *                        \
549                         PCM_##BIT##_BPS) + ch;                                            \
550                     for (i = info->z_size; i != 0; i -= Z_SINC_ACCUMULATE_DECR)           \
551                               Z_SINC_ACCUMULATE(SIGN, BIT, ENDIAN, -);                    \
552                     if (info->z_scale != Z_ONE)                                           \
553                               v = Z_SCALE_##BIT(v, info->z_scale);                        \
554                     else                                                                            \
555                               v >>= Z_COEFF_SHIFT - Z_GUARD_BIT_##BIT;                    \
556                     Z_CLIP_CHECK(v, BIT);                                                           \
557                     _PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst, Z_CLAMP(v, BIT));    \
558           } while (ch != 0);                                                              \
559 }
560 
561 #define Z_DECLARE_SINC_POLYPHASE(SIGN, BIT, ENDIAN)                                       \
562 static void                                                                                         \
563 z_feed_sinc_polyphase_##SIGN##BIT##ENDIAN(struct z_info *info, uint8_t *dst)    \
564 {                                                                                                   \
565           intpcm64_t v;                                                                             \
566           intpcm_t x;                                                                               \
567           uint8_t *p;                                                                               \
568           int32_t ch, i, start, *z_pcoeff;                                                \
569                                                                                                     \
570           ch = info->channels * PCM_##BIT##_BPS;                                          \
571           dst += ch;                                                                                \
572           start = z_prev(info, info->z_start, (info->z_size << 1) - 1) * ch;    \
573                                                                                                     \
574           do {                                                                                      \
575                     dst -= PCM_##BIT##_BPS;                                                         \
576                     ch -= PCM_##BIT##_BPS;                                                          \
577                     v = 0;                                                                          \
578                     p = info->z_delay + start + ch;                                                 \
579                     z_pcoeff = info->z_pcoeff +                                           \
580                         ((info->z_alpha * info->z_size) << 1);                            \
581                     for (i = info->z_size; i != 0; i--) {                                 \
582                               x = _PCM_READ_##SIGN##BIT##_##ENDIAN(p);                    \
583                               v += Z_NORM_##BIT((intpcm64_t)x * *z_pcoeff);               \
584                               z_pcoeff++;                                                           \
585                               p += info->channels * PCM_##BIT##_BPS;                      \
586                               x = _PCM_READ_##SIGN##BIT##_##ENDIAN(p);                    \
587                               v += Z_NORM_##BIT((intpcm64_t)x * *z_pcoeff);               \
588                               z_pcoeff++;                                                           \
589                               p += info->channels * PCM_##BIT##_BPS;                      \
590                     }                                                                               \
591                     if (info->z_scale != Z_ONE)                                           \
592                               v = Z_SCALE_##BIT(v, info->z_scale);                        \
593                     else                                                                            \
594                               v >>= Z_COEFF_SHIFT - Z_GUARD_BIT_##BIT;                    \
595                     Z_CLIP_CHECK(v, BIT);                                                           \
596                     _PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst, Z_CLAMP(v, BIT));    \
597           } while (ch != 0);                                                              \
598 }
599 
600 #define Z_DECLARE(SIGN, BIT, ENDIAN)                                            \
601           Z_DECLARE_LINEAR(SIGN, BIT, ENDIAN)                                   \
602           Z_DECLARE_SINC(SIGN, BIT, ENDIAN)                                     \
603           Z_DECLARE_SINC_POLYPHASE(SIGN, BIT, ENDIAN)
604 
605 #if BYTE_ORDER == LITTLE_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
606 Z_DECLARE(S, 16, LE)
607 Z_DECLARE(S, 32, LE)
608 #endif
609 #if BYTE_ORDER == BIG_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
610 Z_DECLARE(S, 16, BE)
611 Z_DECLARE(S, 32, BE)
612 #endif
613 #ifdef SND_FEEDER_MULTIFORMAT
614 Z_DECLARE(S,  8, NE)
615 Z_DECLARE(S, 24, LE)
616 Z_DECLARE(S, 24, BE)
617 Z_DECLARE(U,  8, NE)
618 Z_DECLARE(U, 16, LE)
619 Z_DECLARE(U, 24, LE)
620 Z_DECLARE(U, 32, LE)
621 Z_DECLARE(U, 16, BE)
622 Z_DECLARE(U, 24, BE)
623 Z_DECLARE(U, 32, BE)
624 #endif
625 
626 enum {
627           Z_RESAMPLER_ZOH,
628           Z_RESAMPLER_LINEAR,
629           Z_RESAMPLER_SINC,
630           Z_RESAMPLER_SINC_POLYPHASE,
631           Z_RESAMPLER_LAST
632 };
633 
634 #define Z_RESAMPLER_IDX(i)                                                      \
635           (Z_IS_SINC(i) ? Z_RESAMPLER_SINC : (i)->quality)
636 
637 #define Z_RESAMPLER_ENTRY(SIGN, BIT, ENDIAN)                                              \
638           {                                                                                         \
639               AFMT_##SIGN##BIT##_##ENDIAN,                                                \
640               {                                                                                     \
641                     [Z_RESAMPLER_ZOH]    = z_feed_zoh,                                    \
642                     [Z_RESAMPLER_LINEAR] = z_feed_linear_##SIGN##BIT##ENDIAN,   \
643                     [Z_RESAMPLER_SINC]   = z_feed_sinc_##SIGN##BIT##ENDIAN,               \
644                     [Z_RESAMPLER_SINC_POLYPHASE]   =                                      \
645                         z_feed_sinc_polyphase_##SIGN##BIT##ENDIAN                         \
646               }                                                                                     \
647           }
648 
649 static const struct {
650           uint32_t format;
651           z_resampler_t resampler[Z_RESAMPLER_LAST];
652 } z_resampler_tab[] = {
653 #if BYTE_ORDER == LITTLE_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
654           Z_RESAMPLER_ENTRY(S, 16, LE),
655           Z_RESAMPLER_ENTRY(S, 32, LE),
656 #endif
657 #if BYTE_ORDER == BIG_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
658           Z_RESAMPLER_ENTRY(S, 16, BE),
659           Z_RESAMPLER_ENTRY(S, 32, BE),
660 #endif
661 #ifdef SND_FEEDER_MULTIFORMAT
662           Z_RESAMPLER_ENTRY(S,  8, NE),
663           Z_RESAMPLER_ENTRY(S, 24, LE),
664           Z_RESAMPLER_ENTRY(S, 24, BE),
665           Z_RESAMPLER_ENTRY(U,  8, NE),
666           Z_RESAMPLER_ENTRY(U, 16, LE),
667           Z_RESAMPLER_ENTRY(U, 24, LE),
668           Z_RESAMPLER_ENTRY(U, 32, LE),
669           Z_RESAMPLER_ENTRY(U, 16, BE),
670           Z_RESAMPLER_ENTRY(U, 24, BE),
671           Z_RESAMPLER_ENTRY(U, 32, BE),
672 #endif
673 };
674 
675 #define Z_RESAMPLER_TAB_SIZE                                                    \
676           ((int32_t)(sizeof(z_resampler_tab) / sizeof(z_resampler_tab[0])))
677 
678 static void
z_resampler_reset(struct z_info * info)679 z_resampler_reset(struct z_info *info)
680 {
681 
682           info->src = info->rsrc - (info->rsrc % ((feeder_rate_round > 0 &&
683               info->rsrc > feeder_rate_round) ? feeder_rate_round : 1));
684           info->dst = info->rdst - (info->rdst % ((feeder_rate_round > 0 &&
685               info->rdst > feeder_rate_round) ? feeder_rate_round : 1));
686           info->z_gx = 1;
687           info->z_gy = 1;
688           info->z_alpha = 0;
689           info->z_resample = NULL;
690           info->z_size = 1;
691           info->z_coeff = NULL;
692           info->z_dcoeff = NULL;
693           if (info->z_pcoeff != NULL) {
694                     kfree(info->z_pcoeff, M_DEVBUF);
695                     info->z_pcoeff = NULL;
696           }
697           info->z_scale = Z_ONE;
698           info->z_dx = Z_FULL_ONE;
699           info->z_dy = Z_FULL_ONE;
700 #ifdef Z_DIAGNOSTIC
701           info->z_cycle = 0;
702 #endif
703           if (info->quality < Z_QUALITY_MIN)
704                     info->quality = Z_QUALITY_MIN;
705           else if (info->quality > Z_QUALITY_MAX)
706                     info->quality = Z_QUALITY_MAX;
707 }
708 
709 #ifdef Z_PARANOID
710 static int32_t
z_resampler_sinc_len(struct z_info * info)711 z_resampler_sinc_len(struct z_info *info)
712 {
713           int32_t c, z, len, lmax;
714 
715           if (!Z_IS_SINC(info))
716                     return (1);
717 
718           /*
719            * A rather careful (or useless) way to calculate filter length.
720            * Z_SINC_LEN() itself is accurate enough to do its job. Extra
721            * sanity checking is not going to hurt though..
722            */
723           c = 0;
724           z = info->z_dy;
725           len = 0;
726           lmax = z_coeff_tab[Z_SINC_COEFF_IDX(info)].len;
727 
728           do {
729                     c += z >> Z_SHIFT;
730                     z &= Z_MASK;
731                     z += info->z_dy;
732           } while (c < lmax && ++len > 0);
733 
734           if (len != Z_SINC_LEN(info)) {
735 #ifdef _KERNEL
736                     kprintf("%s(): sinc l=%d != Z_SINC_LEN=%d\n",
737                         __func__, len, Z_SINC_LEN(info));
738 #else
739                     fprintf(stderr, "%s(): sinc l=%d != Z_SINC_LEN=%d\n",
740                         __func__, len, Z_SINC_LEN(info));
741                     return (-1);
742 #endif
743           }
744 
745           return (len);
746 }
747 #else
748 #define z_resampler_sinc_len(i)                   (Z_IS_SINC(i) ? Z_SINC_LEN(i) : 1)
749 #endif
750 
751 #define Z_POLYPHASE_COEFF_SHIFT                   0
752 
753 /*
754  * Pick suitable polynomial interpolators based on filter oversampled ratio
755  * (2 ^ Z_DRIFT_SHIFT).
756  */
757 #if !(defined(Z_COEFF_INTERP_ZOH) || defined(Z_COEFF_INTERP_LINEAR) ||                    \
758     defined(Z_COEFF_INTERP_QUADRATIC) || defined(Z_COEFF_INTERP_HERMITE) ||     \
759     defined(Z_COEFF_INTER_BSPLINE) || defined(Z_COEFF_INTERP_OPT32X) ||                   \
760     defined(Z_COEFF_INTERP_OPT16X) || defined(Z_COEFF_INTERP_OPT8X) ||                    \
761     defined(Z_COEFF_INTERP_OPT4X) || defined(Z_COEFF_INTERP_OPT2X))
762 #if Z_DRIFT_SHIFT >= 6
763 #define Z_COEFF_INTERP_BSPLINE                    1
764 #elif Z_DRIFT_SHIFT >= 5
765 #define Z_COEFF_INTERP_OPT32X           1
766 #elif Z_DRIFT_SHIFT == 4
767 #define Z_COEFF_INTERP_OPT16X           1
768 #elif Z_DRIFT_SHIFT == 3
769 #define Z_COEFF_INTERP_OPT8X            1
770 #elif Z_DRIFT_SHIFT == 2
771 #define Z_COEFF_INTERP_OPT4X            1
772 #elif Z_DRIFT_SHIFT == 1
773 #define Z_COEFF_INTERP_OPT2X            1
774 #else
775 #error "Z_DRIFT_SHIFT screwed!"
776 #endif
777 #endif
778 
779 /*
780  * In classic polyphase mode, the actual coefficients for each phases need to
781  * be calculated based on default prototype filters. For highly oversampled
782  * filter, linear or quadradatic interpolator should be enough. Anything less
783  * than that require 'special' interpolators to reduce interpolation errors.
784  *
785  * "Polynomial Interpolators for High-Quality Resampling of Oversampled Audio"
786  *    by Olli Niemitalo
787  *    - http://www.student.oulu.fi/~oniemita/dsp/deip.pdf
788  *
789  */
790 static int32_t
z_coeff_interpolate(int32_t z,int32_t * z_coeff)791 z_coeff_interpolate(int32_t z, int32_t *z_coeff)
792 {
793           int32_t coeff;
794 #if defined(Z_COEFF_INTERP_ZOH)
795 
796           /* 1-point, 0th-order (Zero Order Hold) */
797           z = z;
798           coeff = z_coeff[0];
799 #elif defined(Z_COEFF_INTERP_LINEAR)
800           int32_t zl0, zl1;
801 
802           /* 2-point, 1st-order Linear */
803           zl0 = z_coeff[0];
804           zl1 = z_coeff[1] - z_coeff[0];
805 
806           coeff = Z_RSHIFT((int64_t)zl1 * z, Z_SHIFT) + zl0;
807 #elif defined(Z_COEFF_INTERP_QUADRATIC)
808           int32_t zq0, zq1, zq2;
809 
810           /* 3-point, 2nd-order Quadratic */
811           zq0 = z_coeff[0];
812           zq1 = z_coeff[1] - z_coeff[-1];
813           zq2 = z_coeff[1] + z_coeff[-1] - (z_coeff[0] << 1);
814 
815           coeff = Z_RSHIFT((Z_RSHIFT((int64_t)zq2 * z, Z_SHIFT) +
816               zq1) * z, Z_SHIFT + 1) + zq0;
817 #elif defined(Z_COEFF_INTERP_HERMITE)
818           int32_t zh0, zh1, zh2, zh3;
819 
820           /* 4-point, 3rd-order Hermite */
821           zh0 = z_coeff[0];
822           zh1 = z_coeff[1] - z_coeff[-1];
823           zh2 = (z_coeff[-1] << 1) - (z_coeff[0] * 5) + (z_coeff[1] << 2) -
824               z_coeff[2];
825           zh3 = z_coeff[2] - z_coeff[-1] + ((z_coeff[0] - z_coeff[1]) * 3);
826 
827           coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((int64_t)zh3 * z, Z_SHIFT) +
828               zh2) * z, Z_SHIFT) + zh1) * z, Z_SHIFT + 1) + zh0;
829 #elif defined(Z_COEFF_INTERP_BSPLINE)
830           int32_t zb0, zb1, zb2, zb3;
831 
832           /* 4-point, 3rd-order B-Spline */
833           zb0 = Z_RSHIFT(0x15555555LL * (((int64_t)z_coeff[0] << 2) +
834               z_coeff[-1] + z_coeff[1]), 30);
835           zb1 = z_coeff[1] - z_coeff[-1];
836           zb2 = z_coeff[-1] + z_coeff[1] - (z_coeff[0] << 1);
837           zb3 = Z_RSHIFT(0x15555555LL * (((z_coeff[0] - z_coeff[1]) * 3) +
838               z_coeff[2] - z_coeff[-1]), 30);
839 
840           coeff = (Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((int64_t)zb3 * z, Z_SHIFT) +
841               zb2) * z, Z_SHIFT) + zb1) * z, Z_SHIFT) + zb0 + 1) >> 1;
842 #elif defined(Z_COEFF_INTERP_OPT32X)
843           int32_t zoz, zoe1, zoe2, zoe3, zoo1, zoo2, zoo3;
844           int32_t zoc0, zoc1, zoc2, zoc3, zoc4, zoc5;
845 
846           /* 6-point, 5th-order Optimal 32x */
847           zoz = z - (Z_ONE >> 1);
848           zoe1 = z_coeff[1] + z_coeff[0];
849           zoe2 = z_coeff[2] + z_coeff[-1];
850           zoe3 = z_coeff[3] + z_coeff[-2];
851           zoo1 = z_coeff[1] - z_coeff[0];
852           zoo2 = z_coeff[2] - z_coeff[-1];
853           zoo3 = z_coeff[3] - z_coeff[-2];
854 
855           zoc0 = Z_RSHIFT((0x1ac2260dLL * zoe1) + (0x0526cdcaLL * zoe2) +
856               (0x00170c29LL * zoe3), 30);
857           zoc1 = Z_RSHIFT((0x14f8a49aLL * zoo1) + (0x0d6d1109LL * zoo2) +
858               (0x008cd4dcLL * zoo3), 30);
859           zoc2 = Z_RSHIFT((-0x0d3e94a4LL * zoe1) + (0x0bddded4LL * zoe2) +
860               (0x0160b5d0LL * zoe3), 30);
861           zoc3 = Z_RSHIFT((-0x0de10cc4LL * zoo1) + (0x019b2a7dLL * zoo2) +
862               (0x01cfe914LL * zoo3), 30);
863           zoc4 = Z_RSHIFT((0x02aa12d7LL * zoe1) + (-0x03ff1bb3LL * zoe2) +
864               (0x015508ddLL * zoe3), 30);
865           zoc5 = Z_RSHIFT((0x051d29e5LL * zoo1) + (-0x028e7647LL * zoo2) +
866               (0x0082d81aLL * zoo3), 30);
867 
868           coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT(
869               (int64_t)zoc5 * zoz, Z_SHIFT) +
870               zoc4) * zoz, Z_SHIFT) + zoc3) * zoz, Z_SHIFT) +
871               zoc2) * zoz, Z_SHIFT) + zoc1) * zoz, Z_SHIFT) + zoc0;
872 #elif defined(Z_COEFF_INTERP_OPT16X)
873           int32_t zoz, zoe1, zoe2, zoe3, zoo1, zoo2, zoo3;
874           int32_t zoc0, zoc1, zoc2, zoc3, zoc4, zoc5;
875 
876           /* 6-point, 5th-order Optimal 16x */
877           zoz = z - (Z_ONE >> 1);
878           zoe1 = z_coeff[1] + z_coeff[0];
879           zoe2 = z_coeff[2] + z_coeff[-1];
880           zoe3 = z_coeff[3] + z_coeff[-2];
881           zoo1 = z_coeff[1] - z_coeff[0];
882           zoo2 = z_coeff[2] - z_coeff[-1];
883           zoo3 = z_coeff[3] - z_coeff[-2];
884 
885           zoc0 = Z_RSHIFT((0x1ac2260dLL * zoe1) + (0x0526cdcaLL * zoe2) +
886               (0x00170c29LL * zoe3), 30);
887           zoc1 = Z_RSHIFT((0x14f8a49aLL * zoo1) + (0x0d6d1109LL * zoo2) +
888               (0x008cd4dcLL * zoo3), 30);
889           zoc2 = Z_RSHIFT((-0x0d3e94a4LL * zoe1) + (0x0bddded4LL * zoe2) +
890               (0x0160b5d0LL * zoe3), 30);
891           zoc3 = Z_RSHIFT((-0x0de10cc4LL * zoo1) + (0x019b2a7dLL * zoo2) +
892               (0x01cfe914LL * zoo3), 30);
893           zoc4 = Z_RSHIFT((0x02aa12d7LL * zoe1) + (-0x03ff1bb3LL * zoe2) +
894               (0x015508ddLL * zoe3), 30);
895           zoc5 = Z_RSHIFT((0x051d29e5LL * zoo1) + (-0x028e7647LL * zoo2) +
896               (0x0082d81aLL * zoo3), 30);
897 
898           coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT(
899               (int64_t)zoc5 * zoz, Z_SHIFT) +
900               zoc4) * zoz, Z_SHIFT) + zoc3) * zoz, Z_SHIFT) +
901               zoc2) * zoz, Z_SHIFT) + zoc1) * zoz, Z_SHIFT) + zoc0;
902 #elif defined(Z_COEFF_INTERP_OPT8X)
903           int32_t zoz, zoe1, zoe2, zoe3, zoo1, zoo2, zoo3;
904           int32_t zoc0, zoc1, zoc2, zoc3, zoc4, zoc5;
905 
906           /* 6-point, 5th-order Optimal 8x */
907           zoz = z - (Z_ONE >> 1);
908           zoe1 = z_coeff[1] + z_coeff[0];
909           zoe2 = z_coeff[2] + z_coeff[-1];
910           zoe3 = z_coeff[3] + z_coeff[-2];
911           zoo1 = z_coeff[1] - z_coeff[0];
912           zoo2 = z_coeff[2] - z_coeff[-1];
913           zoo3 = z_coeff[3] - z_coeff[-2];
914 
915           zoc0 = Z_RSHIFT((0x1aa9b47dLL * zoe1) + (0x053d9944LL * zoe2) +
916               (0x0018b23fLL * zoe3), 30);
917           zoc1 = Z_RSHIFT((0x14a104d1LL * zoo1) + (0x0d7d2504LL * zoo2) +
918               (0x0094b599LL * zoo3), 30);
919           zoc2 = Z_RSHIFT((-0x0d22530bLL * zoe1) + (0x0bb37a2cLL * zoe2) +
920               (0x016ed8e0LL * zoe3), 30);
921           zoc3 = Z_RSHIFT((-0x0d744b1cLL * zoo1) + (0x01649591LL * zoo2) +
922               (0x01dae93aLL * zoo3), 30);
923           zoc4 = Z_RSHIFT((0x02a7ee1bLL * zoe1) + (-0x03fbdb24LL * zoe2) +
924               (0x0153ed07LL * zoe3), 30);
925           zoc5 = Z_RSHIFT((0x04cf9b6cLL * zoo1) + (-0x0266b378LL * zoo2) +
926               (0x007a7c26LL * zoo3), 30);
927 
928           coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT(
929               (int64_t)zoc5 * zoz, Z_SHIFT) +
930               zoc4) * zoz, Z_SHIFT) + zoc3) * zoz, Z_SHIFT) +
931               zoc2) * zoz, Z_SHIFT) + zoc1) * zoz, Z_SHIFT) + zoc0;
932 #elif defined(Z_COEFF_INTERP_OPT4X)
933           int32_t zoz, zoe1, zoe2, zoe3, zoo1, zoo2, zoo3;
934           int32_t zoc0, zoc1, zoc2, zoc3, zoc4, zoc5;
935 
936           /* 6-point, 5th-order Optimal 4x */
937           zoz = z - (Z_ONE >> 1);
938           zoe1 = z_coeff[1] + z_coeff[0];
939           zoe2 = z_coeff[2] + z_coeff[-1];
940           zoe3 = z_coeff[3] + z_coeff[-2];
941           zoo1 = z_coeff[1] - z_coeff[0];
942           zoo2 = z_coeff[2] - z_coeff[-1];
943           zoo3 = z_coeff[3] - z_coeff[-2];
944 
945           zoc0 = Z_RSHIFT((0x1a8eda43LL * zoe1) + (0x0556ee38LL * zoe2) +
946               (0x001a3784LL * zoe3), 30);
947           zoc1 = Z_RSHIFT((0x143d863eLL * zoo1) + (0x0d910e36LL * zoo2) +
948               (0x009ca889LL * zoo3), 30);
949           zoc2 = Z_RSHIFT((-0x0d026821LL * zoe1) + (0x0b837773LL * zoe2) +
950               (0x017ef0c6LL * zoe3), 30);
951           zoc3 = Z_RSHIFT((-0x0cef1502LL * zoo1) + (0x01207a8eLL * zoo2) +
952               (0x01e936dbLL * zoo3), 30);
953           zoc4 = Z_RSHIFT((0x029fe643LL * zoe1) + (-0x03ef3fc8LL * zoe2) +
954               (0x014f5923LL * zoe3), 30);
955           zoc5 = Z_RSHIFT((0x043a9d08LL * zoo1) + (-0x02154febLL * zoo2) +
956               (0x00670dbdLL * zoo3), 30);
957 
958           coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT(
959               (int64_t)zoc5 * zoz, Z_SHIFT) +
960               zoc4) * zoz, Z_SHIFT) + zoc3) * zoz, Z_SHIFT) +
961               zoc2) * zoz, Z_SHIFT) + zoc1) * zoz, Z_SHIFT) + zoc0;
962 #elif defined(Z_COEFF_INTERP_OPT2X)
963           int32_t zoz, zoe1, zoe2, zoe3, zoo1, zoo2, zoo3;
964           int32_t zoc0, zoc1, zoc2, zoc3, zoc4, zoc5;
965 
966           /* 6-point, 5th-order Optimal 2x */
967           zoz = z - (Z_ONE >> 1);
968           zoe1 = z_coeff[1] + z_coeff[0];
969           zoe2 = z_coeff[2] + z_coeff[-1];
970           zoe3 = z_coeff[3] + z_coeff[-2];
971           zoo1 = z_coeff[1] - z_coeff[0];
972           zoo2 = z_coeff[2] - z_coeff[-1];
973           zoo3 = z_coeff[3] - z_coeff[-2];
974 
975           zoc0 = Z_RSHIFT((0x19edb6fdLL * zoe1) + (0x05ebd062LL * zoe2) +
976               (0x00267881LL * zoe3), 30);
977           zoc1 = Z_RSHIFT((0x1223af76LL * zoo1) + (0x0de3dd6bLL * zoo2) +
978               (0x00d683cdLL * zoo3), 30);
979           zoc2 = Z_RSHIFT((-0x0c3ee068LL * zoe1) + (0x0a5c3769LL * zoe2) +
980               (0x01e2aceaLL * zoe3), 30);
981           zoc3 = Z_RSHIFT((-0x0a8ab614LL * zoo1) + (-0x0019522eLL * zoo2) +
982               (0x022cefc7LL * zoo3), 30);
983           zoc4 = Z_RSHIFT((0x0276187dLL * zoe1) + (-0x03a801e8LL * zoe2) +
984               (0x0131d935LL * zoe3), 30);
985           zoc5 = Z_RSHIFT((0x02c373f5LL * zoo1) + (-0x01275f83LL * zoo2) +
986               (0x0018ee79LL * zoo3), 30);
987 
988           coeff = Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT((Z_RSHIFT(
989               (int64_t)zoc5 * zoz, Z_SHIFT) +
990               zoc4) * zoz, Z_SHIFT) + zoc3) * zoz, Z_SHIFT) +
991               zoc2) * zoz, Z_SHIFT) + zoc1) * zoz, Z_SHIFT) + zoc0;
992 #else
993 #error "Interpolation type screwed!"
994 #endif
995 
996 #if Z_POLYPHASE_COEFF_SHIFT > 0
997           coeff = Z_RSHIFT(coeff, Z_POLYPHASE_COEFF_SHIFT);
998 #endif
999           return (coeff);
1000 }
1001 
1002 static int
z_resampler_build_polyphase(struct z_info * info)1003 z_resampler_build_polyphase(struct z_info *info)
1004 {
1005           int32_t alpha, c, i, z, idx;
1006 
1007           /* Let this be here first. */
1008           if (info->z_pcoeff != NULL) {
1009                     kfree(info->z_pcoeff, M_DEVBUF);
1010                     info->z_pcoeff = NULL;
1011           }
1012 
1013           if (feeder_rate_polyphase_max < 1)
1014                     return (ENOTSUP);
1015 
1016           if (((int64_t)info->z_size * info->z_gy * 2) >
1017               feeder_rate_polyphase_max) {
1018 #ifndef _KERNEL
1019                     fprintf(stderr, "Polyphase entries exceed: [%d/%d] %jd > %d\n",
1020                         info->z_gx, info->z_gy,
1021                         (intmax_t)info->z_size * info->z_gy * 2,
1022                         feeder_rate_polyphase_max);
1023 #endif
1024                     return (E2BIG);
1025           }
1026 
1027           info->z_pcoeff = kmalloc(sizeof(int32_t) *
1028               info->z_size * info->z_gy * 2, M_DEVBUF, M_WAITOK | M_ZERO);
1029           if (info->z_pcoeff == NULL)
1030                     return (ENOMEM);
1031 
1032           for (alpha = 0; alpha < info->z_gy; alpha++) {
1033                     z = alpha * info->z_dx;
1034                     c = 0;
1035                     for (i = info->z_size; i != 0; i--) {
1036                               c += z >> Z_SHIFT;
1037                               z &= Z_MASK;
1038                               idx = (alpha * info->z_size * 2) +
1039                                   (info->z_size * 2) - i;
1040                               info->z_pcoeff[idx] =
1041                                   z_coeff_interpolate(z, info->z_coeff + c);
1042                               z += info->z_dy;
1043                     }
1044                     z = info->z_dy - (alpha * info->z_dx);
1045                     c = 0;
1046                     for (i = info->z_size; i != 0; i--) {
1047                               c += z >> Z_SHIFT;
1048                               z &= Z_MASK;
1049                               idx = (alpha * info->z_size * 2) + i - 1;
1050                               info->z_pcoeff[idx] =
1051                                   z_coeff_interpolate(z, info->z_coeff + c);
1052                               z += info->z_dy;
1053                     }
1054           }
1055 
1056 #ifndef _KERNEL
1057           fprintf(stderr, "Polyphase: [%d/%d] %d entries\n",
1058               info->z_gx, info->z_gy, info->z_size * info->z_gy * 2);
1059 #endif
1060 
1061           return (0);
1062 }
1063 
1064 static int
z_resampler_setup(struct pcm_feeder * f)1065 z_resampler_setup(struct pcm_feeder *f)
1066 {
1067           struct z_info *info;
1068           int64_t gy2gx_max, gx2gy_max;
1069           uint32_t format;
1070           int32_t align, i, z_scale;
1071           int adaptive;
1072 
1073           info = f->data;
1074           z_resampler_reset(info);
1075 
1076           if (info->src == info->dst)
1077                     return (0);
1078 
1079           /* Shrink by greatest common divisor. */
1080           i = z_gcd(info->src, info->dst);
1081           info->z_gx = info->src / i;
1082           info->z_gy = info->dst / i;
1083 
1084           /* Too big, or too small. Bail out. */
1085           if (!(Z_FACTOR_SAFE(info->z_gx) && Z_FACTOR_SAFE(info->z_gy)))
1086                     return (EINVAL);
1087 
1088           format = f->desc->in;
1089           adaptive = 0;
1090           z_scale = 0;
1091 
1092           /*
1093            * Setup everything: filter length, conversion factor, etc.
1094            */
1095           if (Z_IS_SINC(info)) {
1096                     /*
1097                      * Downsampling, or upsampling scaling factor. As long as the
1098                      * factor can be represented by a fraction of 1 << Z_SHIFT,
1099                      * we're pretty much in business. Scaling is not needed for
1100                      * upsampling, so we just slap Z_ONE there.
1101                      */
1102                     if (info->z_gx > info->z_gy)
1103                               /*
1104                                * If the downsampling ratio is beyond sanity,
1105                                * enable semi-adaptive mode. Although handling
1106                                * extreme ratio is possible, the result of the
1107                                * conversion is just pointless, unworthy,
1108                                * nonsensical noises, etc.
1109                                */
1110                               if ((info->z_gx / info->z_gy) > Z_SINC_DOWNMAX)
1111                                         z_scale = Z_ONE / Z_SINC_DOWNMAX;
1112                               else
1113                                         z_scale = ((uint64_t)info->z_gy << Z_SHIFT) /
1114                                             info->z_gx;
1115                     else
1116                               z_scale = Z_ONE;
1117 
1118                     /*
1119                      * This is actually impossible, unless anything above
1120                      * overflow.
1121                      */
1122                     if (z_scale < 1)
1123                               return (E2BIG);
1124 
1125                     /*
1126                      * Calculate sample time/coefficients index drift. It is
1127                      * a constant for upsampling, but downsampling require
1128                      * heavy duty filtering with possible too long filters.
1129                      * If anything goes wrong, revisit again and enable
1130                      * adaptive mode.
1131                      */
1132 z_setup_adaptive_sinc:
1133                     if (info->z_pcoeff != NULL) {
1134                               kfree(info->z_pcoeff, M_DEVBUF);
1135                               info->z_pcoeff = NULL;
1136                     }
1137 
1138                     if (adaptive == 0) {
1139                               info->z_dy = z_scale << Z_DRIFT_SHIFT;
1140                               if (info->z_dy < 1)
1141                                         return (E2BIG);
1142                               info->z_scale = z_scale;
1143                     } else {
1144                               info->z_dy = Z_FULL_ONE;
1145                               info->z_scale = Z_ONE;
1146                     }
1147 
1148 #if 0
1149 #define Z_SCALE_DIV 10000
1150 #define Z_SCALE_LIMIT(s, v)                                                     \
1151           ((((uint64_t)(s) * (v)) + (Z_SCALE_DIV >> 1)) / Z_SCALE_DIV)
1152 
1153                     info->z_scale = Z_SCALE_LIMIT(info->z_scale, 9780);
1154 #endif
1155 
1156                     /* Smallest drift increment. */
1157                     info->z_dx = info->z_dy / info->z_gy;
1158 
1159                     /*
1160                      * Overflow or underflow. Try adaptive, let it continue and
1161                      * retry.
1162                      */
1163                     if (info->z_dx < 1) {
1164                               if (adaptive == 0) {
1165                                         adaptive = 1;
1166                                         goto z_setup_adaptive_sinc;
1167                               }
1168                               return (E2BIG);
1169                     }
1170 
1171                     /*
1172                      * Round back output drift.
1173                      */
1174                     info->z_dy = info->z_dx * info->z_gy;
1175 
1176                     for (i = 0; i < Z_COEFF_TAB_SIZE; i++) {
1177                               if (Z_SINC_COEFF_IDX(info) != i)
1178                                         continue;
1179                               /*
1180                                * Calculate required filter length and guard
1181                                * against possible abusive result. Note that
1182                                * this represents only 1/2 of the entire filter
1183                                * length.
1184                                */
1185                               info->z_size = z_resampler_sinc_len(info);
1186 
1187                               /*
1188                                * Multiple of 2 rounding, for better accumulator
1189                                * performance.
1190                                */
1191                               info->z_size &= ~1;
1192 
1193                               if (info->z_size < 2 || info->z_size > Z_SINC_MAX) {
1194                                         if (adaptive == 0) {
1195                                                   adaptive = 1;
1196                                                   goto z_setup_adaptive_sinc;
1197                                         }
1198                                         return (E2BIG);
1199                               }
1200                               info->z_coeff = z_coeff_tab[i].coeff + Z_COEFF_OFFSET;
1201                               info->z_dcoeff = z_coeff_tab[i].dcoeff;
1202                               break;
1203                     }
1204 
1205                     if (info->z_coeff == NULL || info->z_dcoeff == NULL)
1206                               return (EINVAL);
1207           } else if (Z_IS_LINEAR(info)) {
1208                     /*
1209                      * Don't put much effort if we're doing linear interpolation.
1210                      * Just center the interpolation distance within Z_LINEAR_ONE,
1211                      * and be happy about it.
1212                      */
1213                     info->z_dx = Z_LINEAR_FULL_ONE / info->z_gy;
1214           }
1215 
1216           /*
1217            * We're safe for now, lets continue.. Look for our resampler
1218            * depending on configured format and quality.
1219            */
1220           for (i = 0; i < Z_RESAMPLER_TAB_SIZE; i++) {
1221                     int ridx;
1222 
1223                     if (AFMT_ENCODING(format) != z_resampler_tab[i].format)
1224                               continue;
1225                     if (Z_IS_SINC(info) && adaptive == 0 &&
1226                         z_resampler_build_polyphase(info) == 0)
1227                               ridx = Z_RESAMPLER_SINC_POLYPHASE;
1228                     else
1229                               ridx = Z_RESAMPLER_IDX(info);
1230                     info->z_resample = z_resampler_tab[i].resampler[ridx];
1231                     break;
1232           }
1233 
1234           if (info->z_resample == NULL)
1235                     return (EINVAL);
1236 
1237           info->bps = AFMT_BPS(format);
1238           align = info->channels * info->bps;
1239 
1240           /*
1241            * Calculate largest value that can be fed into z_gy2gx() and
1242            * z_gx2gy() without causing (signed) 32bit overflow. z_gy2gx() will
1243            * be called early during feeding process to determine how much input
1244            * samples that is required to generate requested output, while
1245            * z_gx2gy() will be called just before samples filtering /
1246            * accumulation process based on available samples that has been
1247            * calculated using z_gx2gy().
1248            *
1249            * Now that is damn confusing, I guess ;-) .
1250            */
1251           gy2gx_max = (((uint64_t)info->z_gy * INT32_MAX) - info->z_gy + 1) /
1252               info->z_gx;
1253 
1254           if ((gy2gx_max * align) > SND_FXDIV_MAX)
1255                     gy2gx_max = SND_FXDIV_MAX / align;
1256 
1257           if (gy2gx_max < 1)
1258                     return (E2BIG);
1259 
1260           gx2gy_max = (((uint64_t)info->z_gx * INT32_MAX) - info->z_gy) /
1261               info->z_gy;
1262 
1263           if (gx2gy_max > INT32_MAX)
1264                     gx2gy_max = INT32_MAX;
1265 
1266           if (gx2gy_max < 1)
1267                     return (E2BIG);
1268 
1269           /*
1270            * Ensure that z_gy2gx() at its largest possible calculated value
1271            * (alpha = 0) will not cause overflow further late during z_gx2gy()
1272            * stage.
1273            */
1274           if (z_gy2gx(info, gy2gx_max) > _Z_GCAST(gx2gy_max))
1275                     return (E2BIG);
1276 
1277           info->z_maxfeed = gy2gx_max * align;
1278 
1279 #ifdef Z_USE_ALPHADRIFT
1280           info->z_startdrift = z_gy2gx(info, 1);
1281           info->z_alphadrift = z_drift(info, info->z_startdrift, 1);
1282 #endif
1283 
1284           i = z_gy2gx(info, 1);
1285           info->z_full = z_roundpow2((info->z_size << 1) + i);
1286 
1287           /*
1288            * Too big to be true, and overflowing left and right like mad ..
1289            */
1290           if ((info->z_full * align) < 1) {
1291                     if (adaptive == 0 && Z_IS_SINC(info)) {
1292                               adaptive = 1;
1293                               goto z_setup_adaptive_sinc;
1294                     }
1295                     return (E2BIG);
1296           }
1297 
1298           /*
1299            * Increase full buffer size if its too small to reduce cyclic
1300            * buffer shifting in main conversion/feeder loop.
1301            */
1302           while (info->z_full < Z_RESERVOIR_MAX &&
1303               (info->z_full - (info->z_size << 1)) < Z_RESERVOIR)
1304                     info->z_full <<= 1;
1305 
1306           /* Initialize buffer position. */
1307           info->z_mask = info->z_full - 1;
1308           info->z_start = z_prev(info, info->z_size << 1, 1);
1309           info->z_pos = z_next(info, info->z_start, 1);
1310 
1311           /*
1312            * Allocate or reuse delay line buffer, whichever makes sense.
1313            */
1314           i = info->z_full * align;
1315           if (i < 1)
1316                     return (E2BIG);
1317 
1318           if (info->z_delay == NULL || info->z_alloc < i ||
1319               i <= (info->z_alloc >> 1)) {
1320                     if (info->z_delay != NULL)
1321                               kfree(info->z_delay, M_DEVBUF);
1322                     info->z_delay = kmalloc(i, M_DEVBUF, M_WAITOK | M_ZERO);
1323                     if (info->z_delay == NULL)
1324                               return (ENOMEM);
1325                     info->z_alloc = i;
1326           }
1327 
1328           /*
1329            * Zero out head of buffer to avoid pops and clicks.
1330            */
1331           memset(info->z_delay, sndbuf_zerodata(f->desc->out),
1332               info->z_pos * align);
1333 
1334 #ifdef Z_DIAGNOSTIC
1335           /*
1336            * XXX Debuging mess !@#$%^
1337            */
1338 #define dumpz(x)    fprintf(stderr, "\t%12s = %10u : %-11d\n",        \
1339                                   "z_"__STRING(x), (uint32_t)info->z_##x,       \
1340                                   (int32_t)info->z_##x)
1341           fprintf(stderr, "\n%s():\n", __func__);
1342           fprintf(stderr, "\tchannels=%d, bps=%d, format=0x%08x, quality=%d\n",
1343               info->channels, info->bps, format, info->quality);
1344           fprintf(stderr, "\t%d (%d) -> %d (%d), ",
1345               info->src, info->rsrc, info->dst, info->rdst);
1346           fprintf(stderr, "[%d/%d]\n", info->z_gx, info->z_gy);
1347           fprintf(stderr, "\tminreq=%d, ", z_gy2gx(info, 1));
1348           if (adaptive != 0)
1349                     z_scale = Z_ONE;
1350           fprintf(stderr, "factor=0x%08x/0x%08x (%f)\n",
1351               z_scale, Z_ONE, (double)z_scale / Z_ONE);
1352           fprintf(stderr, "\tbase_length=%d, ", Z_SINC_BASE_LEN(info));
1353           fprintf(stderr, "adaptive=%s\n", (adaptive != 0) ? "YES" : "NO");
1354           dumpz(size);
1355           dumpz(alloc);
1356           if (info->z_alloc < 1024)
1357                     fprintf(stderr, "\t%15s%10d Bytes\n",
1358                         "", info->z_alloc);
1359           else if (info->z_alloc < (1024 << 10))
1360                     fprintf(stderr, "\t%15s%10d KBytes\n",
1361                         "", info->z_alloc >> 10);
1362           else if (info->z_alloc < (1024 << 20))
1363                     fprintf(stderr, "\t%15s%10d MBytes\n",
1364                         "", info->z_alloc >> 20);
1365           else
1366                     fprintf(stderr, "\t%15s%10d GBytes\n",
1367                         "", info->z_alloc >> 30);
1368           fprintf(stderr, "\t%12s   %10d (min output samples)\n",
1369               "",
1370               (int32_t)z_gx2gy(info, info->z_full - (info->z_size << 1)));
1371           fprintf(stderr, "\t%12s   %10d (min allocated output samples)\n",
1372               "",
1373               (int32_t)z_gx2gy(info, (info->z_alloc / align) -
1374               (info->z_size << 1)));
1375           fprintf(stderr, "\t%12s = %10d\n",
1376               "z_gy2gx()", (int32_t)z_gy2gx(info, 1));
1377           fprintf(stderr, "\t%12s = %10d -> z_gy2gx() -> %d\n",
1378               "Max", (int32_t)gy2gx_max, (int32_t)z_gy2gx(info, gy2gx_max));
1379           fprintf(stderr, "\t%12s = %10d\n",
1380               "z_gx2gy()", (int32_t)z_gx2gy(info, 1));
1381           fprintf(stderr, "\t%12s = %10d -> z_gx2gy() -> %d\n",
1382               "Max", (int32_t)gx2gy_max, (int32_t)z_gx2gy(info, gx2gy_max));
1383           dumpz(maxfeed);
1384           dumpz(full);
1385           dumpz(start);
1386           dumpz(pos);
1387           dumpz(scale);
1388           fprintf(stderr, "\t%12s   %10f\n", "",
1389               (double)info->z_scale / Z_ONE);
1390           dumpz(dx);
1391           fprintf(stderr, "\t%12s   %10f\n", "",
1392               (double)info->z_dx / info->z_dy);
1393           dumpz(dy);
1394           fprintf(stderr, "\t%12s   %10d (drift step)\n", "",
1395               info->z_dy >> Z_SHIFT);
1396           fprintf(stderr, "\t%12s   %10d (scaling differences)\n", "",
1397               (z_scale << Z_DRIFT_SHIFT) - info->z_dy);
1398           fprintf(stderr, "\t%12s = %u bytes\n",
1399               "intpcm32_t", sizeof(intpcm32_t));
1400           fprintf(stderr, "\t%12s = 0x%08x, smallest=%.16lf\n",
1401               "Z_ONE", Z_ONE, (double)1.0 / (double)Z_ONE);
1402 #endif
1403 
1404           return (0);
1405 }
1406 
1407 static int
z_resampler_set(struct pcm_feeder * f,int what,int32_t value)1408 z_resampler_set(struct pcm_feeder *f, int what, int32_t value)
1409 {
1410           struct z_info *info;
1411           int32_t oquality;
1412 
1413           info = f->data;
1414 
1415           switch (what) {
1416           case Z_RATE_SRC:
1417                     if (value < feeder_rate_min || value > feeder_rate_max)
1418                               return (E2BIG);
1419                     if (value == info->rsrc)
1420                               return (0);
1421                     info->rsrc = value;
1422                     break;
1423           case Z_RATE_DST:
1424                     if (value < feeder_rate_min || value > feeder_rate_max)
1425                               return (E2BIG);
1426                     if (value == info->rdst)
1427                               return (0);
1428                     info->rdst = value;
1429                     break;
1430           case Z_RATE_QUALITY:
1431                     if (value < Z_QUALITY_MIN || value > Z_QUALITY_MAX)
1432                               return (EINVAL);
1433                     if (value == info->quality)
1434                               return (0);
1435                     /*
1436                      * If we failed to set the requested quality, restore
1437                      * the old one. We cannot afford leaving it broken since
1438                      * passive feeder chains like vchans never reinitialize
1439                      * itself.
1440                      */
1441                     oquality = info->quality;
1442                     info->quality = value;
1443                     if (z_resampler_setup(f) == 0)
1444                               return (0);
1445                     info->quality = oquality;
1446                     break;
1447           case Z_RATE_CHANNELS:
1448                     if (value < SND_CHN_MIN || value > SND_CHN_MAX)
1449                               return (EINVAL);
1450                     if (value == info->channels)
1451                               return (0);
1452                     info->channels = value;
1453                     break;
1454           default:
1455                     return (EINVAL);
1456                     break;
1457           }
1458 
1459           return (z_resampler_setup(f));
1460 }
1461 
1462 static int
z_resampler_get(struct pcm_feeder * f,int what)1463 z_resampler_get(struct pcm_feeder *f, int what)
1464 {
1465           struct z_info *info;
1466 
1467           info = f->data;
1468 
1469           switch (what) {
1470           case Z_RATE_SRC:
1471                     return (info->rsrc);
1472                     break;
1473           case Z_RATE_DST:
1474                     return (info->rdst);
1475                     break;
1476           case Z_RATE_QUALITY:
1477                     return (info->quality);
1478                     break;
1479           case Z_RATE_CHANNELS:
1480                     return (info->channels);
1481                     break;
1482           default:
1483                     break;
1484           }
1485 
1486           return (-1);
1487 }
1488 
1489 static int
z_resampler_init(struct pcm_feeder * f)1490 z_resampler_init(struct pcm_feeder *f)
1491 {
1492           struct z_info *info;
1493           int ret;
1494 
1495           if (f->desc->in != f->desc->out)
1496                     return (EINVAL);
1497 
1498           info = kmalloc(sizeof(*info), M_DEVBUF, M_WAITOK | M_ZERO);
1499           if (info == NULL)
1500                     return (ENOMEM);
1501 
1502           info->rsrc = Z_RATE_DEFAULT;
1503           info->rdst = Z_RATE_DEFAULT;
1504           info->quality = feeder_rate_quality;
1505           info->channels = AFMT_CHANNEL(f->desc->in);
1506 
1507           f->data = info;
1508 
1509           ret = z_resampler_setup(f);
1510           if (ret != 0) {
1511                     if (info->z_pcoeff != NULL)
1512                               kfree(info->z_pcoeff, M_DEVBUF);
1513                     if (info->z_delay != NULL)
1514                               kfree(info->z_delay, M_DEVBUF);
1515                     kfree(info, M_DEVBUF);
1516                     f->data = NULL;
1517           }
1518 
1519           return (ret);
1520 }
1521 
1522 static int
z_resampler_free(struct pcm_feeder * f)1523 z_resampler_free(struct pcm_feeder *f)
1524 {
1525           struct z_info *info;
1526 
1527           info = f->data;
1528           if (info != NULL) {
1529                     if (info->z_pcoeff != NULL)
1530                               kfree(info->z_pcoeff, M_DEVBUF);
1531                     if (info->z_delay != NULL)
1532                               kfree(info->z_delay, M_DEVBUF);
1533                     kfree(info, M_DEVBUF);
1534           }
1535 
1536           f->data = NULL;
1537 
1538           return (0);
1539 }
1540 
1541 static uint32_t
z_resampler_feed_internal(struct pcm_feeder * f,struct pcm_channel * c,uint8_t * b,uint32_t count,void * source)1542 z_resampler_feed_internal(struct pcm_feeder *f, struct pcm_channel *c,
1543     uint8_t *b, uint32_t count, void *source)
1544 {
1545           struct z_info *info;
1546           int32_t alphadrift, startdrift, reqout, ocount, reqin, align;
1547           int32_t fetch, fetched, start, cp;
1548           uint8_t *dst;
1549 
1550           info = f->data;
1551           if (info->z_resample == NULL)
1552                     return (z_feed(f->source, c, b, count, source));
1553 
1554           /*
1555            * Calculate sample size alignment and amount of sample output.
1556            * We will do everything in sample domain, but at the end we
1557            * will jump back to byte domain.
1558            */
1559           align = info->channels * info->bps;
1560           ocount = SND_FXDIV(count, align);
1561           if (ocount == 0)
1562                     return (0);
1563 
1564           /*
1565            * Calculate amount of input samples that is needed to generate
1566            * exact amount of output.
1567            */
1568           reqin = z_gy2gx(info, ocount) - z_fetched(info);
1569 
1570 #ifdef Z_USE_ALPHADRIFT
1571           startdrift = info->z_startdrift;
1572           alphadrift = info->z_alphadrift;
1573 #else
1574           startdrift = _Z_GY2GX(info, 0, 1);
1575           alphadrift = z_drift(info, startdrift, 1);
1576 #endif
1577 
1578           dst = b;
1579 
1580           do {
1581                     if (reqin != 0) {
1582                               fetch = z_min(z_free(info), reqin);
1583                               if (fetch == 0) {
1584                                         /*
1585                                          * No more free spaces, so wind enough
1586                                          * samples back to the head of delay line
1587                                          * in byte domain.
1588                                          */
1589                                         fetched = z_fetched(info);
1590                                         start = z_prev(info, info->z_start,
1591                                             (info->z_size << 1) - 1);
1592                                         cp = (info->z_size << 1) + fetched;
1593                                         z_copy(info->z_delay + (start * align),
1594                                             info->z_delay, cp * align);
1595                                         info->z_start =
1596                                             z_prev(info, info->z_size << 1, 1);
1597                                         info->z_pos =
1598                                             z_next(info, info->z_start, fetched + 1);
1599                                         fetch = z_min(z_free(info), reqin);
1600 #ifdef Z_DIAGNOSTIC
1601                                         if (1) {
1602                                                   static uint32_t kk = 0;
1603                                                   fprintf(stderr,
1604                                                       "Buffer Move: "
1605                                                       "start=%d fetched=%d cp=%d "
1606                                                       "cycle=%u [%u]\r",
1607                                                       start, fetched, cp, info->z_cycle,
1608                                                       ++kk);
1609                                         }
1610                                         info->z_cycle = 0;
1611 #endif
1612                               }
1613                               if (fetch != 0) {
1614                                         /*
1615                                          * Fetch in byte domain and jump back
1616                                          * to sample domain.
1617                                          */
1618                                         fetched = SND_FXDIV(z_feed(f->source, c,
1619                                             info->z_delay + (info->z_pos * align),
1620                                             fetch * align, source), align);
1621                                         /*
1622                                          * Prepare to convert fetched buffer,
1623                                          * or mark us done if we cannot fulfill
1624                                          * the request.
1625                                          */
1626                                         reqin -= fetched;
1627                                         info->z_pos += fetched;
1628                                         if (fetched != fetch)
1629                                                   reqin = 0;
1630                               }
1631                     }
1632 
1633                     reqout = z_min(z_gx2gy(info, z_fetched(info)), ocount);
1634                     if (reqout != 0) {
1635                               ocount -= reqout;
1636 
1637                               /*
1638                                * Drift.. drift.. drift..
1639                                *
1640                                * Notice that there are 2 methods of doing the drift
1641                                * operations: The former is much cleaner (in a sense
1642                                * of mathematical readings of my eyes), but slower
1643                                * due to integer division in z_gy2gx(). Nevertheless,
1644                                * both should give the same exact accurate drifting
1645                                * results, so the later is favourable.
1646                                */
1647                               do {
1648                                         info->z_resample(info, dst);
1649 #if 0
1650                                         startdrift = z_gy2gx(info, 1);
1651                                         alphadrift = z_drift(info, startdrift, 1);
1652                                         info->z_start += startdrift;
1653                                         info->z_alpha += alphadrift;
1654 #else
1655                                         info->z_alpha += alphadrift;
1656                                         if (info->z_alpha < info->z_gy)
1657                                                   info->z_start += startdrift;
1658                                         else {
1659                                                   info->z_start += startdrift - 1;
1660                                                   info->z_alpha -= info->z_gy;
1661                                         }
1662 #endif
1663                                         dst += align;
1664 #ifdef Z_DIAGNOSTIC
1665                                         info->z_cycle++;
1666 #endif
1667                               } while (--reqout != 0);
1668                     }
1669           } while (reqin != 0 && ocount != 0);
1670 
1671           /*
1672            * Back to byte domain..
1673            */
1674           return (dst - b);
1675 }
1676 
1677 static int
z_resampler_feed(struct pcm_feeder * f,struct pcm_channel * c,uint8_t * b,uint32_t count,void * source)1678 z_resampler_feed(struct pcm_feeder *f, struct pcm_channel *c, uint8_t *b,
1679     uint32_t count, void *source)
1680 {
1681           uint32_t feed, maxfeed, left;
1682 
1683           /*
1684            * Split count to smaller chunks to avoid possible 32bit overflow.
1685            */
1686           maxfeed = ((struct z_info *)(f->data))->z_maxfeed;
1687           left = count;
1688 
1689           do {
1690                     feed = z_resampler_feed_internal(f, c, b,
1691                         z_min(maxfeed, left), source);
1692                     b += feed;
1693                     left -= feed;
1694           } while (left != 0 && feed != 0);
1695 
1696           return (count - left);
1697 }
1698 
1699 static struct pcm_feederdesc feeder_rate_desc[] = {
1700           { FEEDER_RATE, 0, 0, 0, 0 },
1701           { 0, 0, 0, 0, 0 },
1702 };
1703 
1704 static kobj_method_t feeder_rate_methods[] = {
1705           KOBJMETHOD(feeder_init,                 z_resampler_init),
1706           KOBJMETHOD(feeder_free,                 z_resampler_free),
1707           KOBJMETHOD(feeder_set,                  z_resampler_set),
1708           KOBJMETHOD(feeder_get,                  z_resampler_get),
1709           KOBJMETHOD(feeder_feed,                 z_resampler_feed),
1710           KOBJMETHOD_END
1711 };
1712 
1713 FEEDER_DECLARE(feeder_rate, NULL);
1714