![[BACK]](/cvsweb/icons/back.gif){kind=icon}
Return to pcspk.c CVS log ![[TXT]](/cvsweb/icons/text.gif){kind=icon}
![[DIR]](/cvsweb/icons/dir.gif){kind=icon}
Up to [Qemu by Fabrice Bellard] / qemu / hw|
Return to pcspk.c CVS log | Up to [Qemu by Fabrice Bellard] / qemu / hw |
1.1 root 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:
1.1.1.3 root 25: #include "hw.h"
26: #include "pc.h"
27: #include "isa.h"
28: #include "audio/audio.h"
29: #include "qemu-timer.h"
1.1 root 30:
31: #define PCSPK_BUF_LEN 1792
32: #define PCSPK_SAMPLE_RATE 32000
33: #define PCSPK_MAX_FREQ (PCSPK_SAMPLE_RATE >> 1)
34: #define PCSPK_MIN_COUNT ((PIT_FREQ + PCSPK_MAX_FREQ - 1) / PCSPK_MAX_FREQ)
35:
36: typedef struct {
37: uint8_t sample_buf[PCSPK_BUF_LEN];
38: QEMUSoundCard card;
39: SWVoiceOut *voice;
40: PITState *pit;
41: unsigned int pit_count;
42: unsigned int samples;
43: unsigned int play_pos;
44: int data_on;
45: int dummy_refresh_clock;
46: } PCSpkState;
47:
48: static const char *s_spk = "pcspk";
49: static PCSpkState pcspk_state;
50:
51: static inline void generate_samples(PCSpkState *s)
52: {
53: unsigned int i;
54:
55: if (s->pit_count) {
56: const uint32_t m = PCSPK_SAMPLE_RATE * s->pit_count;
57: const uint32_t n = ((uint64_t)PIT_FREQ << 32) / m;
58:
59: /* multiple of wavelength for gapless looping */
60: s->samples = (PCSPK_BUF_LEN * PIT_FREQ / m * m / (PIT_FREQ >> 1) + 1) >> 1;
61: for (i = 0; i < s->samples; ++i)
62: s->sample_buf[i] = (64 & (n * i >> 25)) - 32;
63: } else {
64: s->samples = PCSPK_BUF_LEN;
65: for (i = 0; i < PCSPK_BUF_LEN; ++i)
66: s->sample_buf[i] = 128; /* silence */
67: }
68: }
69:
70: static void pcspk_callback(void *opaque, int free)
71: {
72: PCSpkState *s = opaque;
73: unsigned int n;
74:
75: if (pit_get_mode(s->pit, 2) != 3)
76: return;
77:
78: n = pit_get_initial_count(s->pit, 2);
79: /* avoid frequencies that are not reproducible with sample rate */
80: if (n < PCSPK_MIN_COUNT)
81: n = 0;
82:
83: if (s->pit_count != n) {
84: s->pit_count = n;
85: s->play_pos = 0;
86: generate_samples(s);
87: }
88:
89: while (free > 0) {
90: n = audio_MIN(s->samples - s->play_pos, (unsigned int)free);
91: n = AUD_write(s->voice, &s->sample_buf[s->play_pos], n);
92: if (!n)
93: break;
94: s->play_pos = (s->play_pos + n) % s->samples;
95: free -= n;
96: }
97: }
98:
1.1.1.3 root 99: int pcspk_audio_init(AudioState *audio, qemu_irq *pic)
1.1 root 100: {
101: PCSpkState *s = &pcspk_state;
1.1.1.4 ! root 102: struct audsettings as = {PCSPK_SAMPLE_RATE, 1, AUD_FMT_U8, 0};
1.1 root 103:
104: if (!audio) {
105: AUD_log(s_spk, "No audio state\n");
106: return -1;
107: }
108: AUD_register_card(audio, s_spk, &s->card);
109:
1.1.1.2 root 110: s->voice = AUD_open_out(&s->card, s->voice, s_spk, s, pcspk_callback, &as);
1.1 root 111: if (!s->voice) {
112: AUD_log(s_spk, "Could not open voice\n");
113: return -1;
114: }
115:
116: return 0;
117: }
118:
119: static uint32_t pcspk_ioport_read(void *opaque, uint32_t addr)
120: {
121: PCSpkState *s = opaque;
122: int out;
123:
124: s->dummy_refresh_clock ^= (1 << 4);
125: out = pit_get_out(s->pit, 2, qemu_get_clock(vm_clock)) << 5;
126:
127: return pit_get_gate(s->pit, 2) | (s->data_on << 1) | s->dummy_refresh_clock | out;
128: }
129:
130: static void pcspk_ioport_write(void *opaque, uint32_t addr, uint32_t val)
131: {
132: PCSpkState *s = opaque;
133: const int gate = val & 1;
134:
135: s->data_on = (val >> 1) & 1;
136: pit_set_gate(s->pit, 2, gate);
137: if (s->voice) {
138: if (gate) /* restart */
139: s->play_pos = 0;
140: AUD_set_active_out(s->voice, gate & s->data_on);
141: }
142: }
143:
144: void pcspk_init(PITState *pit)
145: {
146: PCSpkState *s = &pcspk_state;
147:
148: s->pit = pit;
149: register_ioport_read(0x61, 1, 1, pcspk_ioport_read, s);
150: register_ioport_write(0x61, 1, 1, pcspk_ioport_write, s);
151: }
This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.