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1 /*
2 * QEMU PC speaker emulation
3 *
4 * Copyright (c) 2006 Joachim Henke
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24
25 #include "qemu/osdep.h"
26 #include "hw/isa/isa.h"
27 #include "hw/audio/model.h"
28 #include "qemu/audio.h"
29 #include "qemu/module.h"
30 #include "qemu/timer.h"
31 #include "qemu/error-report.h"
32 #include "hw/timer/i8254.h"
33 #include "migration/vmstate.h"
34 #include "hw/audio/pcspk.h"
35 #include "qapi/error.h"
36 #include "qom/object.h"
37 #include "trace.h"
38
39 #define PCSPK_BUF_LEN 1792
40 #define PCSPK_SAMPLE_RATE 32000
41 #define PCSPK_MAX_FREQ (PCSPK_SAMPLE_RATE >> 1)
42 #define PCSPK_MIN_COUNT DIV_ROUND_UP(PIT_FREQ, PCSPK_MAX_FREQ)
43
44 OBJECT_DECLARE_SIMPLE_TYPE(PCSpkState, PC_SPEAKER)
45
46 struct PCSpkState {
47 ISADevice parent_obj;
48
49 MemoryRegion ioport;
50 uint32_t iobase;
51 uint8_t sample_buf[PCSPK_BUF_LEN];
52 AudioBackend *audio_be;
53 SWVoiceOut *voice;
54 PITCommonState *pit;
55 unsigned int pit_count;
56 unsigned int samples;
57 unsigned int play_pos;
58 uint8_t data_on;
59 uint8_t dummy_refresh_clock;
60 };
61
62 static const char *s_spk = "pcspk";
63
64 static inline void generate_samples(PCSpkState *s)
65 {
66 unsigned int i;
67
68 if (s->pit_count) {
69 const uint32_t m = PCSPK_SAMPLE_RATE * s->pit_count;
70 const uint32_t n = ((uint64_t)PIT_FREQ << 32) / m;
71
72 /* multiple of wavelength for gapless looping */
73 s->samples = (QEMU_ALIGN_DOWN(PCSPK_BUF_LEN * PIT_FREQ, m) / (PIT_FREQ >> 1) + 1) >> 1;
74 for (i = 0; i < s->samples; ++i)
75 s->sample_buf[i] = (64 & (n * i >> 25)) - 32;
76 } else {
77 s->samples = PCSPK_BUF_LEN;
78 for (i = 0; i < PCSPK_BUF_LEN; ++i)
79 s->sample_buf[i] = 128; /* silence */
80 }
81 }
82
83 static void pcspk_callback(void *opaque, int free)
84 {
85 PCSpkState *s = opaque;
86 PITChannelInfo ch;
87 unsigned int n;
88
89 pit_get_channel_info(s->pit, 2, &ch);
90
91 if (ch.mode != 3) {
92 return;
93 }
94
95 n = ch.initial_count;
96 /* avoid frequencies that are not reproducible with sample rate */
97 if (n < PCSPK_MIN_COUNT)
98 n = 0;
99
100 if (s->pit_count != n) {
101 s->pit_count = n;
102 s->play_pos = 0;
103 generate_samples(s);
104 }
105
106 while (free > 0) {
107 n = MIN(s->samples - s->play_pos, (unsigned int)free);
108 n = audio_be_write(s->audio_be, s->voice, &s->sample_buf[s->play_pos], n);
109 if (!n)
110 break;
111 s->play_pos = (s->play_pos + n) % s->samples;
112 free -= n;
113 }
114 }
115
116 static int pcspk_audio_init(PCSpkState *s)
117 {
118 struct audsettings as = {PCSPK_SAMPLE_RATE, 1, AUDIO_FORMAT_U8, 0};
119
120 if (s->voice) {
121 /* already initialized */
122 return 0;
123 }
124
125 s->voice = audio_be_open_out(s->audio_be, s->voice, s_spk, s, pcspk_callback, &as);
126 if (!s->voice) {
127 error_report("pcspk: Could not open voice");
128 return -1;
129 }
130
131 return 0;
132 }
133
134 static uint64_t pcspk_io_read(void *opaque, hwaddr addr,
135 unsigned size)
136 {
137 PCSpkState *s = opaque;
138 PITChannelInfo ch;
139 uint8_t val;
140
141 pit_get_channel_info(s->pit, 2, &ch);
142
143 s->dummy_refresh_clock ^= (1 << 4);
144
145 val = ch.gate | (s->data_on << 1) | s->dummy_refresh_clock |
146 (ch.out << 5);
147
148 trace_pcspk_io_read(s->iobase, val);
149
150 return val;
151 }
152
153 static void pcspk_io_write(void *opaque, hwaddr addr, uint64_t val,
154 unsigned size)
155 {
156 PCSpkState *s = opaque;
157 const int gate = val & 1;
158
159 trace_pcspk_io_write(s->iobase, val);
160
161 s->data_on = (val >> 1) & 1;
162 pit_set_gate(s->pit, 2, gate);
163 if (s->voice) {
164 if (gate) /* restart */
165 s->play_pos = 0;
166 audio_be_set_active_out(s->audio_be, s->voice, gate & s->data_on);
167 }
168 }
169
170 static const MemoryRegionOps pcspk_io_ops = {
171 .read = pcspk_io_read,
172 .write = pcspk_io_write,
173 .impl = {
174 .min_access_size = 1,
175 .max_access_size = 1,
176 },
177 };
178
179 static void pcspk_initfn(Object *obj)
180 {
181 PCSpkState *s = PC_SPEAKER(obj);
182
183 memory_region_init_io(&s->ioport, OBJECT(s), &pcspk_io_ops, s, "pcspk", 1);
184 }
185
186 static void pcspk_realizefn(DeviceState *dev, Error **errp)
187 {
188 ISADevice *isadev = ISA_DEVICE(dev);
189 PCSpkState *s = PC_SPEAKER(dev);
190
191 if (!s->pit) {
192 error_setg(errp, "pcspk: No \"pit\" set or available");
193 return;
194 }
195
196 isa_register_ioport(isadev, &s->ioport, s->iobase);
197
198 if (s->audio_be && audio_be_check(&s->audio_be, errp)) {
199 pcspk_audio_init(s);
200 return;
201 }
202 }
203
204 static const VMStateDescription vmstate_spk = {
205 .name = "pcspk",
206 .version_id = 1,
207 .minimum_version_id = 1,
208 .fields = (const VMStateField[]) {
209 VMSTATE_UINT8(data_on, PCSpkState),
210 VMSTATE_UINT8(dummy_refresh_clock, PCSpkState),
211 VMSTATE_END_OF_LIST()
212 }
213 };
214
215 static const Property pcspk_properties[] = {
216 DEFINE_AUDIO_PROPERTIES(PCSpkState, audio_be),
217 DEFINE_PROP_UINT32("iobase", PCSpkState, iobase, 0x61),
218 DEFINE_PROP_LINK("pit", PCSpkState, pit, TYPE_PIT_COMMON, PITCommonState *),
219 };
220
221 static void pcspk_class_initfn(ObjectClass *klass, const void *data)
222 {
223 DeviceClass *dc = DEVICE_CLASS(klass);
224
225 dc->realize = pcspk_realizefn;
226 set_bit(DEVICE_CATEGORY_SOUND, dc->categories);
227 dc->vmsd = &vmstate_spk;
228 device_class_set_props(dc, pcspk_properties);
229 /* Reason: pit object link */
230 dc->user_creatable = false;
231 }
232
233 static const TypeInfo pcspk_info = {
234 .name = TYPE_PC_SPEAKER,
235 .parent = TYPE_ISA_DEVICE,
236 .instance_size = sizeof(PCSpkState),
237 .instance_init = pcspk_initfn,
238 .class_init = pcspk_class_initfn,
239 };
240
241 static void pcspk_register(void)
242 {
243 type_register_static(&pcspk_info);
244 }
245 type_init(pcspk_register)