1 /* $NetBSD: psgpam_enc.c,v 1.3 2023/01/15 05:08:33 tsutsui Exp $ */
2
3 /*
4 * Copyright (c) 2018 Yosuke Sugahara. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
20 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
21 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
22 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28 /*
29 * PSGPAM, PSGPCM encoders
30 * Function names are PSGPAM, but also used by PSGPCM.
31 *
32 * PSGPAM and PSGPCM internally use the unsigned type auint_t for
33 * intermediate calculations to manage non-linear conversions.
34 */
35
36 #include <sys/types.h>
37
38 #if defined(_KERNEL)
39 #include <sys/device.h>
40 #include <sys/audioio.h>
41 #include <dev/audio/audio_if.h>
42 #include <luna68k/dev/psgpam_enc.h>
43 #include <luna68k/dev/psgpam_table.h>
44 #else
45 #include <stdint.h>
46 #include <stdlib.h>
47 #include "audio/userland.h"
48 #include "psgpam_enc.h"
49 #include "psgpam_table.c"
50 #include "psgpam_table.h"
51 #endif
52
53 void
psgpam_init_context(struct psgpam_codecvar * ctx,u_int sample_rate)54 psgpam_init_context(struct psgpam_codecvar *ctx, u_int sample_rate)
55 {
56
57 ctx->offset = 65535;
58 ctx->sample_rate = sample_rate;
59 ctx->expire_initial = sample_rate / 10;
60 ctx->expire = ctx->expire_initial;
61 }
62
63 static inline auint_t
dynamic_offset(struct psgpam_codecvar * ctx,auint_t v)64 dynamic_offset(struct psgpam_codecvar *ctx, auint_t v)
65 {
66
67 /*
68 * if (the passed value cannot be handled by current offset) {
69 * update offset to handle the passed value
70 * } else {
71 * increment offset
72 * }
73 */
74 if (v <= ctx->offset) {
75 ctx->offset = v;
76 } else {
77 if (--ctx->expire < 0) {
78 ctx->offset += 1;
79 ctx->expire = ctx->expire_initial;
80 }
81 }
82 return v - ctx->offset;
83 }
84
85 #define BULK(table) *d++ = table[v]
86
87 #define W8(table) *d++ = table[v]
88
89 #define W16(table) do { \
90 uint16_t t = (uint16_t)table[v]; \
91 *d++ = ((t & 0xf0) << 4) | (t & 0x0f); \
92 } while (0)
93
94 #define W32(table) do { \
95 uint32_t t = (uint32_t)table[v]; \
96 *d++ = ((t & 0xf000) << 12) \
97 | ((t & 0x0f00) << 8) \
98 | ((t & 0x00f0) << 4) \
99 | ((t & 0x000f)); \
100 } while (0)
101
102 #define SPLIT3(table) do { \
103 uint16_t t = (uint16_t)table[v]; \
104 *d++ = ((t & 0xf000) >> 12); \
105 *d++ = ((t & 0x0f00) >> 8); \
106 *d++ = ((t & 0x000f)); \
107 } while (0)
108
109 #define ENCODER_DEFINE(enc, TT, table, writer) \
110 void \
111 psgpam_aint_to_##enc(audio_filter_arg_t *arg) \
112 { \
113 const aint_t *s = arg->src; \
114 TT *d = arg->dst; \
115 \
116 for (int i = 0; i < arg->count; i++) { \
117 auint_t v = (*s++) ^ AINT_T_MIN; \
118 v >>= (AUDIO_INTERNAL_BITS - table##_BITS); \
119 writer(table); \
120 } \
121 }
122
123 #define ENCODER_D_DEFINE(enc, TT, table, writer) \
124 void \
125 psgpam_aint_to_##enc##_d(audio_filter_arg_t *arg) \
126 { \
127 const aint_t *s = arg->src; \
128 TT *d = arg->dst; \
129 \
130 for (int i = 0; i < arg->count; i++) { \
131 auint_t v = (*s++) ^ AINT_T_MIN; \
132 v >>= (AUDIO_INTERNAL_BITS - table##_BITS); \
133 v = dynamic_offset(arg->context, v); \
134 writer(table); \
135 } \
136 }
137
138 ENCODER_DEFINE(pam2a, uint16_t, PAM2A_TABLE, W16)
139 ENCODER_DEFINE(pam2b, uint16_t, PAM2B_TABLE, W16)
140 ENCODER_DEFINE(pam3a, uint32_t, PAM3A_TABLE, W32)
141 ENCODER_DEFINE(pam3b, uint32_t, PAM3B_TABLE, W32)
142 ENCODER_DEFINE(pcm1, uint8_t, PCM1_TABLE, W8)
143 ENCODER_DEFINE(pcm2, uint16_t, PCM2_TABLE, W16)
144 ENCODER_DEFINE(pcm3, uint8_t, PCM3_TABLE, SPLIT3)
145
146 ENCODER_D_DEFINE(pam2a, uint16_t, PAM2A_TABLE, W16)
147 ENCODER_D_DEFINE(pam2b, uint16_t, PAM2B_TABLE, W16)
148 ENCODER_D_DEFINE(pam3a, uint32_t, PAM3A_TABLE, W32)
149 ENCODER_D_DEFINE(pam3b, uint32_t, PAM3B_TABLE, W32)
150 ENCODER_D_DEFINE(pcm1, uint8_t, PCM1_TABLE, W8)
151 ENCODER_D_DEFINE(pcm2, uint16_t, PCM2_TABLE, W16)
152 ENCODER_D_DEFINE(pcm3, uint8_t, PCM3_TABLE, SPLIT3)
153