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-rw-r--r--src/hw/audio/pcspk.c213
1 files changed, 213 insertions, 0 deletions
diff --git a/src/hw/audio/pcspk.c b/src/hw/audio/pcspk.c
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+/*
+ * QEMU PC speaker emulation
+ *
+ * Copyright (c) 2006 Joachim Henke
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "hw/hw.h"
+#include "hw/i386/pc.h"
+#include "hw/isa/isa.h"
+#include "hw/audio/audio.h"
+#include "audio/audio.h"
+#include "qemu/timer.h"
+#include "hw/timer/i8254.h"
+#include "hw/audio/pcspk.h"
+
+#define PCSPK_BUF_LEN 1792
+#define PCSPK_SAMPLE_RATE 32000
+#define PCSPK_MAX_FREQ (PCSPK_SAMPLE_RATE >> 1)
+#define PCSPK_MIN_COUNT ((PIT_FREQ + PCSPK_MAX_FREQ - 1) / PCSPK_MAX_FREQ)
+
+#define PC_SPEAKER(obj) OBJECT_CHECK(PCSpkState, (obj), TYPE_PC_SPEAKER)
+
+typedef struct {
+ ISADevice parent_obj;
+
+ MemoryRegion ioport;
+ uint32_t iobase;
+ uint8_t sample_buf[PCSPK_BUF_LEN];
+ QEMUSoundCard card;
+ SWVoiceOut *voice;
+ void *pit;
+ unsigned int pit_count;
+ unsigned int samples;
+ unsigned int play_pos;
+ int data_on;
+ int dummy_refresh_clock;
+} PCSpkState;
+
+static const char *s_spk = "pcspk";
+static PCSpkState *pcspk_state;
+
+static inline void generate_samples(PCSpkState *s)
+{
+ unsigned int i;
+
+ if (s->pit_count) {
+ const uint32_t m = PCSPK_SAMPLE_RATE * s->pit_count;
+ const uint32_t n = ((uint64_t)PIT_FREQ << 32) / m;
+
+ /* multiple of wavelength for gapless looping */
+ s->samples = (PCSPK_BUF_LEN * PIT_FREQ / m * m / (PIT_FREQ >> 1) + 1) >> 1;
+ for (i = 0; i < s->samples; ++i)
+ s->sample_buf[i] = (64 & (n * i >> 25)) - 32;
+ } else {
+ s->samples = PCSPK_BUF_LEN;
+ for (i = 0; i < PCSPK_BUF_LEN; ++i)
+ s->sample_buf[i] = 128; /* silence */
+ }
+}
+
+static void pcspk_callback(void *opaque, int free)
+{
+ PCSpkState *s = opaque;
+ PITChannelInfo ch;
+ unsigned int n;
+
+ pit_get_channel_info(s->pit, 2, &ch);
+
+ if (ch.mode != 3) {
+ return;
+ }
+
+ n = ch.initial_count;
+ /* avoid frequencies that are not reproducible with sample rate */
+ if (n < PCSPK_MIN_COUNT)
+ n = 0;
+
+ if (s->pit_count != n) {
+ s->pit_count = n;
+ s->play_pos = 0;
+ generate_samples(s);
+ }
+
+ while (free > 0) {
+ n = audio_MIN(s->samples - s->play_pos, (unsigned int)free);
+ n = AUD_write(s->voice, &s->sample_buf[s->play_pos], n);
+ if (!n)
+ break;
+ s->play_pos = (s->play_pos + n) % s->samples;
+ free -= n;
+ }
+}
+
+static int pcspk_audio_init(ISABus *bus)
+{
+ PCSpkState *s = pcspk_state;
+ struct audsettings as = {PCSPK_SAMPLE_RATE, 1, AUD_FMT_U8, 0};
+
+ AUD_register_card(s_spk, &s->card);
+
+ s->voice = AUD_open_out(&s->card, s->voice, s_spk, s, pcspk_callback, &as);
+ if (!s->voice) {
+ AUD_log(s_spk, "Could not open voice\n");
+ return -1;
+ }
+
+ return 0;
+}
+
+static uint64_t pcspk_io_read(void *opaque, hwaddr addr,
+ unsigned size)
+{
+ PCSpkState *s = opaque;
+ PITChannelInfo ch;
+
+ pit_get_channel_info(s->pit, 2, &ch);
+
+ s->dummy_refresh_clock ^= (1 << 4);
+
+ return ch.gate | (s->data_on << 1) | s->dummy_refresh_clock |
+ (ch.out << 5);
+}
+
+static void pcspk_io_write(void *opaque, hwaddr addr, uint64_t val,
+ unsigned size)
+{
+ PCSpkState *s = opaque;
+ const int gate = val & 1;
+
+ s->data_on = (val >> 1) & 1;
+ pit_set_gate(s->pit, 2, gate);
+ if (s->voice) {
+ if (gate) /* restart */
+ s->play_pos = 0;
+ AUD_set_active_out(s->voice, gate & s->data_on);
+ }
+}
+
+static const MemoryRegionOps pcspk_io_ops = {
+ .read = pcspk_io_read,
+ .write = pcspk_io_write,
+ .impl = {
+ .min_access_size = 1,
+ .max_access_size = 1,
+ },
+};
+
+static void pcspk_initfn(Object *obj)
+{
+ PCSpkState *s = PC_SPEAKER(obj);
+
+ memory_region_init_io(&s->ioport, OBJECT(s), &pcspk_io_ops, s, "pcspk", 1);
+}
+
+static void pcspk_realizefn(DeviceState *dev, Error **errp)
+{
+ ISADevice *isadev = ISA_DEVICE(dev);
+ PCSpkState *s = PC_SPEAKER(dev);
+
+ isa_register_ioport(isadev, &s->ioport, s->iobase);
+
+ pcspk_state = s;
+}
+
+static Property pcspk_properties[] = {
+ DEFINE_PROP_UINT32("iobase", PCSpkState, iobase, -1),
+ DEFINE_PROP_PTR("pit", PCSpkState, pit),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void pcspk_class_initfn(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->realize = pcspk_realizefn;
+ set_bit(DEVICE_CATEGORY_SOUND, dc->categories);
+ dc->props = pcspk_properties;
+ /* Reason: pointer property "pit", realize sets global pcspk_state */
+ dc->cannot_instantiate_with_device_add_yet = true;
+}
+
+static const TypeInfo pcspk_info = {
+ .name = TYPE_PC_SPEAKER,
+ .parent = TYPE_ISA_DEVICE,
+ .instance_size = sizeof(PCSpkState),
+ .instance_init = pcspk_initfn,
+ .class_init = pcspk_class_initfn,
+};
+
+static void pcspk_register(void)
+{
+ type_register_static(&pcspk_info);
+ isa_register_soundhw("pcspk", "PC speaker", pcspk_audio_init);
+}
+type_init(pcspk_register)
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