[Qemu-devel] [PATCH v3 20/25] pc98sound: add NEC PC-9821 family sound (PC-9801-86)

[TAKEDA, toshiya]

diff --git a/qemu/hw/pc98sound.c b/qemu/hw/pc98sound.c
new file mode 100644
index 0000000..3ec36b0
--- /dev/null
+++ b/qemu/hw/pc98sound.c
@@ -0,0 +1,697 @@
+/*
+ * QEMU Proxy for YM2608 emulation by MAME team
+ * QEMU NEC PC-9821 Sound (PC-9801-86)
+ *
+ * Copyright (c) 2004-2005 Vassili Karpov (malc)
+ * Copyright (c) 2009 TAKEDA, toshiya
+ *
+ * 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.h"
+#include "audio/audio.h"
+#include "pc.h"
+#include "isa.h"
+#include "qemu-timer.h"
+#include "ym2608intf.h"
+
+#define SOUND_SAMPLE_RATE 44100
+#define SHIFT 1
+
+#define PCM86_SAMPLE_RATE 44100
+#define PCM86_FIFO_SIZE 0x8000
+
+#define YM2608_CLOCK 3993552
+#define YM2608_CLOCK_2 (YM2608_CLOCK << 1)
+#define YM2608_PCM_SIZE 0x40000
+
+typedef struct {
+    QEMUSoundCard card;
+    int enabled;
+    int active;
+    int16_t *mix_buf;
+    int16_t *ym2608_buf[2];
+    int16_t *ay8910_buf[3];
+    int16_t *pcm86_buf;
+    uint8_t mix_vol[8];
+    uint8_t ym2608_mask;
+    uint8_t ym2608_ticking[2];
+    double ym2608_err[2];
+    uint8_t pcm86_fifo[PCM86_FIFO_SIZE];
+    int pcm86_fifo_count;
+    int pcm86_fifo_write, pcm86_fifo_read;
+    int16_t pcm86_data;
+    int pcm86_ptr;
+    uint8_t pcm86_fifo_ctrl;
+    uint8_t pcm86_dac_ctrl;
+    uint8_t pcm86_irq_timing;
+    uint8_t pcm86_mute;
+    int pcm86_lr, pcm86_lr_half;
+    uint8_t irq_ym2608, irq_pcm86;
+    uint8_t irq_status;
+    SWVoiceOut *voice;
+    int left, pos, samples;
+    int pre_samples;
+    QEMUAudioTimeStamp ats;
+    QEMUTimer *qemu_timer[2];
+    int64_t update_clock;
+    qemu_irq irq;
+} sound_t;
+
+typedef struct sound_isabus_t {
+    ISADevice dev;
+    uint32_t isairq;
+    sound_t state;
+} sound_isabus_t;
+
+static sound_isabus_t *glob_isa;
+static uint8_t ym2608_pcm_buf[YM2608_PCM_SIZE];
+
+static void update_irq(void *opaque);
+static void sound_mix(int samples);
+
+/* ym2608 */
+
+static void ym2608_stop_timer(int c)
+{
+    sound_t *s = &glob_isa->state;
+
+    s->ym2608_ticking[c] = 0;
+    YM2608TimerOver(0, c);
+}
+
+static void qemu_timer_a_handler(void *opaque)
+{
+    ym2608_stop_timer(0);
+}
+
+static void qemu_timer_b_handler(void *opaque)
+{
+    ym2608_stop_timer(1);
+}
+
+static void ym2608_timer_handler(int c, int clock)
+{
+    sound_t *s = &glob_isa->state;
+
+    if (clock == 0) {
+        if (s->ym2608_ticking[c]) {
+            qemu_del_timer(s->qemu_timer[c]);
+            s->ym2608_ticking[c] = 0;
+        }
+    } else {
+        if (!s->ym2608_ticking[c]) {
+            double ms = 1000. * clock / (double)YM2608_CLOCK_2 + 
s->ym2608_err[c];
+            int ms_int = (int)ms;
+            s->ym2608_err[c] = ms - ms_int;
+            if (ms_int > 0) {
+                qemu_mod_timer(s->qemu_timer[c], qemu_get_clock(rt_clock) + 
ms_int);
+                s->ym2608_ticking[c] = 1;
+            } else {
+                ym2608_stop_timer(c);
+            }
+        }
+    }
+}
+
+static void ym2608_irq_handler(int irq)
+{
+    sound_t *s = &glob_isa->state;
+
+    s->irq_ym2608 = (irq != 0);
+    update_irq(s);
+}
+
+static void ym2608_update_handler(void)
+{
+    sound_t *s = &glob_isa->state;
+
+    if (s->update_clock == -1) {
+        s->update_clock = qemu_get_clock(rt_clock);;
+    } else {
+        int64_t current = qemu_get_clock(rt_clock);
+        int64_t period = current - s->update_clock;
+        int64_t samples = muldiv64(SOUND_SAMPLE_RATE, period, 1000);
+        if (samples) {
+            sound_mix(samples);
+            s->update_clock = current;
+        }
+    }
+}
+
+static uint8_t ym2608_port_a_read(uint32_t offset)
+{
+    return 0xff; /* INT5 */
+}
+
+static void ym2608_port_b_write(uint32_t offset, uint8 data)
+{
+}
+
+static void ym2608_ioport_write(void *opaque, uint32_t nport, uint32_t val)
+{
+    sound_t *s = opaque;
+
+    if (nport == 0xa460) {
+        s->ym2608_mask = val;
+    } else {
+        s->active = 1;
+        AUD_set_active_out(s->voice, 1);
+
+        YM2608Write(0, (nport >> 1) & 0x03, val);
+    }
+}
+
+static uint32_t ym2608_ioport_read(void *opaque, uint32_t nport)
+{
+    if (nport == 0xa460) {
+        return 0x41; /* PC-9801-86 */
+    } else {
+        return YM2608Read(0, (nport >> 1) & 0x03);
+    }
+}
+
+/* pcm */
+
+static void pcm86_fifo_write(void *opaque, uint8_t val)
+{
+    sound_t *s = opaque;
+
+    if (s->pcm86_fifo_count < PCM86_FIFO_SIZE) {
+        s->pcm86_fifo[s->pcm86_fifo_write++] = val;
+        s->pcm86_fifo_write &= (PCM86_FIFO_SIZE - 1);
+        s->pcm86_fifo_count++;
+    }
+}
+
+static uint8_t pcm86_fifo_read(void *opaque)
+{
+    sound_t *s = opaque;
+    uint8_t val = 0;
+
+    if (s->pcm86_fifo_count > 0) {
+        val = s->pcm86_fifo[s->pcm86_fifo_read++];
+        s->pcm86_fifo_read &= (PCM86_FIFO_SIZE - 1);
+        s->pcm86_fifo_count--;
+    }
+    return val;
+}
+
+static int16_t pcm86_fifo_read8(void *opaque)
+{
+    sound_t *s = opaque;
+
+    return (int16_t)(pcm86_fifo_read(s) << 8);
+}
+
+static int16_t pcm86_fifo_read16(void *opaque)
+{
+    sound_t *s = opaque;
+    uint16_t val = 0;
+
+    if (s->pcm86_fifo_count > 1) {
+        val = pcm86_fifo_read(s) << 8;
+        val |= pcm86_fifo_read(s);
+    }
+    return (int16_t)val;
+}
+
+/* 0 = 44.10kHz    PCM86_SAMPLE_RATE * 96 / 96
+   1 = 33.08kHz    PCM86_SAMPLE_RATE * 72 / 96
+   2 = 22.05kHz    PCM86_SAMPLE_RATE * 48 / 96
+   3 = 16.54kHz    PCM86_SAMPLE_RATE * 36 / 96
+   4 = 11.03kHz    PCM86_SAMPLE_RATE * 24 / 96
+   5 =  8.27kHz    PCM86_SAMPLE_RATE * 16 / 96
+   6 =  5.52kHz    PCM86_SAMPLE_RATE * 12 / 96
+   7 =  4.13kHz    PCM86_SAMPLE_RATE *  9 / 96
+*/
+static const int pcm86_freq_table[8] = {96, 72, 48, 36, 24, 16, 12, 9};
+
+#define PCM86_DISABLE(s) ((s->pcm86_dac_ctrl & 0x30) == 0x00)
+#define PCM86_MONO_R(s) ((s->pcm86_dac_ctrl & 0x30) == 0x10)
+#define PCM86_MONO_L(s) ((s->pcm86_dac_ctrl & 0x30) == 0x20)
+#define PCM86_STEREO(s) ((s->pcm86_dac_ctrl & 0x30) == 0x30)
+#define PCM86_8BIT(s) ((s->pcm86_dac_ctrl & 0x40) != 0x00)
+
+#define PCM86_FIFO_ENB(s) ((s->pcm86_fifo_ctrl & 0x80) != 0x00)
+#define PCM86_FIFO_PLAY(s) ((s->pcm86_fifo_ctrl & 0x40) == 0x00)
+#define PCM86_FIFO_REC(s) ((s->pcm86_fifo_ctrl & 0x40) != 0x00)
+#define PCM86_FIFO_EI(s) ((s->pcm86_fifo_ctrl & 0x20) != 0x00)
+
+static void pcm86_mix(void *opaque, int16_t *buffer, int samples)
+{
+    sound_t *s = opaque;
+    int i;
+    int add = pcm86_freq_table[s->pcm86_fifo_ctrl & 0x07];
+
+    if (PCM86_DISABLE(s) || !(PCM86_FIFO_ENB(s) && PCM86_FIFO_PLAY(s))) {
+        memset(buffer, 0, sizeof(int16_t) * samples);
+        return;
+    }
+    for (i = 0; i < samples; i++) {
+        if ((s->pcm86_ptr += add) >= 96) {
+            int16_t l, r;
+            if (PCM86_8BIT(s)) {
+                l = pcm86_fifo_read8(s);
+                r = pcm86_fifo_read8(s);
+            } else {
+                l = pcm86_fifo_read16(s);
+                r = pcm86_fifo_read16(s);
+            }
+            if (s->pcm86_mute) {
+                s->pcm86_data = 0;
+            } else if (PCM86_MONO_L(s)) {
+                s->pcm86_data = l;
+            } else if (PCM86_MONO_R(s)) {
+                s->pcm86_data = r;
+            } else {
+                s->pcm86_data = (l + r) >> 1; /* XXX: stereo -> mono */
+            }
+            s->pcm86_ptr -= 96;
+            /* irq */
+            s->irq_pcm86 = (s->pcm86_fifo_count <= 128 * s->pcm86_irq_timing);
+            if (PCM86_FIFO_EI(s)) {
+                update_irq(s);
+            }
+        }
+        buffer[i] = s->pcm86_data;
+    }
+}
+
+static void pcm86_ioport_write(void *opaque, uint32_t nport, uint32_t val)
+{
+    sound_t *s = opaque;
+
+    switch (nport) {
+    case 0xa466:
+        s->mix_vol[val >> 5] = val & 0x0f;
+        break;
+    case 0xa468:
+        s->pcm86_fifo_ctrl = val;
+        if (val & 0x08) {
+            s->pcm86_fifo_count = 0;
+            s->pcm86_fifo_write = s->pcm86_fifo_read = 0;
+        }
+        if (!(val & 0x10) && s->irq_pcm86) {
+            s->irq_pcm86 = 0;
+            update_irq(s);
+        }
+        /* ticks_per_sample */
+        s->pcm86_lr = PCM86_SAMPLE_RATE * pcm86_freq_table[val & 0x07] / 96;
+        s->pcm86_lr = get_ticks_per_sec() / s->pcm86_lr;
+        s->pcm86_lr_half = s->pcm86_lr >> 1;
+        break;
+    case 0xa46a:
+        if (s->pcm86_fifo_ctrl & 0x20) {
+            s->pcm86_irq_timing = val;
+        } else {
+            s->pcm86_dac_ctrl = val;
+        }
+        break;
+    case 0xa46c:
+        pcm86_fifo_write(s, val);
+        break;
+    case 0xa66e:
+        s->pcm86_mute = val & 1;
+    }
+}
+
+static uint32_t pcm86_ioport_read(void *opaque, uint32_t nport)
+{
+    sound_t *s = opaque;
+    uint32_t val = 0;
+
+    switch (nport) {
+    case 0xa466:
+        if (s->pcm86_fifo_count == PCM86_FIFO_SIZE) {
+            val |= 0x80;
+        }
+        if (s->pcm86_fifo_count == 0) {
+            val |= 0x40;
+        }
+        if (s->pcm86_lr) {
+            if ((qemu_get_clock(vm_clock) % s->pcm86_lr) < s->pcm86_lr_half) {
+                val |= 0x01;
+            }
+        }
+        return val;
+    case 0xa468:
+        if (s->irq_pcm86) {
+            return s->pcm86_fifo_ctrl | 0x10;
+        } else {
+            return s->pcm86_fifo_ctrl & (~0x10);
+        }
+    case 0xa46a:
+        return s->pcm86_dac_ctrl;
+    case 0xa46c:
+        return pcm86_fifo_read(s);
+    case 0xa66e:
+        return s->pcm86_mute;
+    }
+    return 0xff;
+}
+
+/* irq */
+
+static void update_irq(void *opaque)
+{
+    sound_t *s = opaque;
+    uint8_t irq_new = 0;
+
+    if (s->irq_ym2608 || (s->irq_pcm86 && PCM86_FIFO_EI(s))) {
+        irq_new = 1;
+    }
+    if (s->irq_status != irq_new) {
+        s->irq_status = irq_new;
+        qemu_set_irq(s->irq, s->irq_status);
+    }
+}
+
+/* sound */
+
+static void sound_mix(int samples)
+{
+    sound_t *s = &glob_isa->state;
+    int i, limit = s->samples - (s->pos + s->pre_samples);
+
+    if (samples > limit) {
+        samples = limit;
+    }
+    if (samples > 0) {
+        YM2608UpdateOne(0, s->ym2608_buf, samples);
+        AY8910Update(0, s->ay8910_buf, samples);
+        pcm86_mix(s, s->pcm86_buf, samples);
+        for (i = 0; i < samples; i++) {
+            /* XXX: mixer volume */
+            int32_t data = 0;
+            data += s->ym2608_buf[0][i] * 3;// * 2;
+            data += s->ym2608_buf[1][i] * 3;// * 2;
+            data += s->ay8910_buf[0][i] * 2;
+            data += s->ay8910_buf[1][i] * 2;
+            data += s->ay8910_buf[2][i] * 2;
+            data += s->pcm86_buf[i] * 12;
+            data >>= 4;
+            if (data > 32767) {
+                data = 32767;
+            } else if (data < -32768) {
+                data = -32768;
+            }
+            s->mix_buf[s->pos + s->pre_samples + i] = data;
+        }
+        s->pre_samples += samples;
+    }
+}
+
+static int write_audio(sound_t *s, int samples)
+{
+    int net = 0;
+    int pos = s->pos;
+
+    while (samples) {
+        int nbytes, wbytes, wsampl;
+
+        nbytes = samples << SHIFT;
+        wbytes = AUD_write(s->voice, s->mix_buf + (pos << (SHIFT - 1)), 
nbytes);
+
+        if (wbytes) {
+            wsampl = wbytes >> SHIFT;
+
+            samples -= wsampl;
+            pos = (pos + wsampl) % s->samples;
+
+            net += wsampl;
+        } else {
+            break;
+        }
+    }
+
+    return net;
+}
+
+static void sound_callback(void *opaque, int free)
+{
+    sound_t *s = opaque;
+    int samples, to_play, written;
+
+    samples = free >> SHIFT;
+    if (!(s->active && s->enabled) || !samples) {
+        return;
+    }
+
+    to_play = audio_MIN(s->left, samples);
+    while (to_play) {
+        written = write_audio(s, to_play);
+
+        if (written) {
+            s->left -= written;
+            samples -= written;
+            to_play -= written;
+            s->pos = (s->pos + written) % s->samples;
+        } else {
+            return;
+        }
+    }
+
+    samples = audio_MIN(samples, s->samples - s->pos);
+    if (!samples) {
+        return;
+    }
+
+    if (s->pre_samples > samples) {
+        s->pre_samples -= samples;
+    } else {
+        sound_mix(samples - s->pre_samples);
+        s->pre_samples = 0;
+        s->update_clock = qemu_get_clock(rt_clock);
+    }
+
+    while (samples) {
+        written = write_audio(s, samples);
+
+        if (written) {
+            samples -= written;
+            s->pos = (s->pos + written) % s->samples;
+        } else {
+            s->left = samples;
+            return;
+        }
+    }
+}
+
+/* initialize */
+
+static void pc98_sound_save(QEMUFile* f, void *opaque)
+{
+    sound_t *s = opaque;
+
+    YM2608_sh_save_state(f);
+
+    qemu_put_buffer(f, s->mix_vol, sizeof(s->mix_vol));
+    qemu_put_8s(f, &s->ym2608_mask);
+    qemu_put_buffer(f, s->ym2608_ticking, sizeof(s->ym2608_ticking));
+    qemu_put_buffer(f, s->pcm86_fifo, sizeof(s->pcm86_fifo));
+    qemu_put_be32s(f, &s->pcm86_fifo_count);
+    qemu_put_be32s(f, &s->pcm86_fifo_write);
+    qemu_put_be32s(f, &s->pcm86_fifo_read);
+    qemu_put_be16s(f, &s->pcm86_data);
+    qemu_put_8s(f, &s->pcm86_fifo_ctrl);
+    qemu_put_8s(f, &s->pcm86_dac_ctrl);
+    qemu_put_8s(f, &s->pcm86_irq_timing);
+    qemu_put_8s(f, &s->pcm86_mute);
+    qemu_put_be32s(f, &s->pcm86_lr);
+    qemu_put_be32s(f, &s->pcm86_lr_half);
+    qemu_put_8s(f, &s->irq_ym2608);
+    qemu_put_8s(f, &s->irq_pcm86);
+    qemu_put_8s(f, &s->irq_status);
+}
+
+static int pc98_sound_load(QEMUFile* f, void *opaque, int version_id)
+{
+    sound_t *s = opaque;
+
+    YM2608_sh_load_state(f);
+    YM2608_sh_postload();
+
+    qemu_get_buffer(f, s->mix_vol, sizeof(s->mix_vol));
+    qemu_get_8s(f, &s->ym2608_mask);
+    qemu_get_buffer(f, s->ym2608_ticking, sizeof(s->ym2608_ticking));
+    qemu_get_buffer(f, s->pcm86_fifo, sizeof(s->pcm86_fifo));
+    qemu_get_be32s(f, &s->pcm86_fifo_count);
+    qemu_get_be32s(f, &s->pcm86_fifo_write);
+    qemu_get_be32s(f, &s->pcm86_fifo_read);
+    qemu_get_be16s(f, &s->pcm86_data);
+    qemu_get_8s(f, &s->pcm86_fifo_ctrl);
+    qemu_get_8s(f, &s->pcm86_dac_ctrl);
+    qemu_get_8s(f, &s->pcm86_irq_timing);
+    qemu_get_8s(f, &s->pcm86_mute);
+    qemu_get_be32s(f, &s->pcm86_lr);
+    qemu_get_be32s(f, &s->pcm86_lr_half);
+    qemu_get_8s(f, &s->irq_ym2608);
+    qemu_get_8s(f, &s->irq_pcm86);
+    qemu_get_8s(f, &s->irq_status);
+
+    s->ym2608_err[0] = s->ym2608_err[1] = 0.0;
+    s->pcm86_ptr = 0;
+    s->left = s->pos = s->samples = 0;
+    s->pre_samples = 0;
+    s->update_clock = -1;
+
+    return 0;
+}
+
+static struct YM2608interface ym2608_interface =
+{
+    1,
+    YM2608_CLOCK,
+    { ym2608_port_a_read },
+    { 0 }, // port-b read handler
+    { 0 }, // port-a write handler
+    { ym2608_port_b_write },
+    { ym2608_irq_handler },
+    { ym2608_timer_handler },
+    { ym2608_update_handler },
+    { ym2608_pcm_buf },
+    { YM2608_PCM_SIZE },
+};
+
+static struct MachineSound machine_sound =
+{
+    1,
+    &ym2608_interface,
+    "YM2608",
+};
+
+static void sound_release(void *opaque)
+{
+    sound_t *s = opaque;
+
+    YM2608_sh_stop();
+
+    if (s->ym2608_buf[0]) {
+        qemu_free(s->ym2608_buf[0]);
+    }
+    if (s->ym2608_buf[1]) {
+        qemu_free(s->ym2608_buf[1]);
+    }
+    if (s->ay8910_buf[0]) {
+        qemu_free(s->ay8910_buf[0]);
+    }
+    if (s->ay8910_buf[1]) {
+        qemu_free(s->ay8910_buf[1]);
+    }
+    if (s->ay8910_buf[2]) {
+        qemu_free(s->ay8910_buf[2]);
+    }
+    if (s->mix_buf) {
+        qemu_free(s->mix_buf);
+    }
+
+    s->active = 0;
+    s->enabled = 0;
+    AUD_remove_card(&s->card);
+}
+
+static int pc98_sound_initfn(ISADevice *dev)
+{
+    static int pcm86_nport[5] = { 0xa466, 0xa468, 0xa46a, 0xa46c, 0xa66e };
+    sound_isabus_t *isa = DO_UPCAST(sound_isabus_t, dev, dev);
+    sound_t *s = &isa->state;
+    struct audsettings as;
+    int i;
+
+    glob_isa = isa;
+
+    YM2608_sh_start(&machine_sound, SOUND_SAMPLE_RATE);
+    s->enabled = 1;
+
+    as.freq = SOUND_SAMPLE_RATE;
+    as.nchannels = SHIFT;
+    as.fmt = AUD_FMT_S16;
+    as.endianness = AUDIO_HOST_ENDIANNESS;
+
+    AUD_register_card("ym2608", &s->card);
+
+    s->voice = AUD_open_out(&s->card, s->voice,
+                            "ym2608", s, sound_callback, &as);
+    if (!s->voice) {
+        sound_release(s);
+        return -1;
+    }
+
+    s->samples = AUD_get_buffer_size_out(s->voice) >> SHIFT;
+    s->mix_buf = qemu_mallocz(s->samples << SHIFT);
+    s->ym2608_buf[0] = qemu_mallocz(s->samples << SHIFT);
+    s->ym2608_buf[1] = qemu_mallocz(s->samples << SHIFT);
+    s->ay8910_buf[0] = qemu_mallocz(s->samples << SHIFT);
+    s->ay8910_buf[1] = qemu_mallocz(s->samples << SHIFT);
+    s->ay8910_buf[2] = qemu_mallocz(s->samples << SHIFT);
+    s->pcm86_buf = qemu_mallocz(s->samples << SHIFT);
+
+    memset(ym2608_pcm_buf, 0, sizeof(ym2608_pcm_buf));
+
+    for (i = 0; i < 4; i++) {
+        register_ioport_read(0x188 + (i << 1), 1, 1, ym2608_ioport_read, s);
+        register_ioport_write(0x188 + (i << 1), 1, 1, ym2608_ioport_write, s);
+    }
+    register_ioport_read(0xa460, 1, 1, ym2608_ioport_read, s);
+    register_ioport_write(0xa460, 1, 1, ym2608_ioport_write, s);
+
+    for (i = 0; i < 5; i++) {
+        register_ioport_read(pcm86_nport[i], 1, 1, pcm86_ioport_read, s);
+        register_ioport_write(pcm86_nport[i], 1, 1, pcm86_ioport_write, s);
+    }
+
+    isa_init_irq(dev, &s->irq, isa->isairq);
+
+    s->qemu_timer[0] = qemu_new_timer(rt_clock, qemu_timer_a_handler, s);
+    s->qemu_timer[1] = qemu_new_timer(rt_clock, qemu_timer_b_handler, s);
+
+    s->update_clock = -1;
+
+    register_savevm("pc98-sound", 0, 1, pc98_sound_save, pc98_sound_load, s);
+
+    return 0;
+}
+
+int pc98_sound_init(qemu_irq *pic)
+{
+    ISADevice *dev;
+
+    dev = isa_create("pc98-sound");
+    qdev_init_nofail(&dev->qdev);
+
+    return 0;
+}
+
+static ISADeviceInfo pc98_sound_info = {
+    .qdev.name  = "pc98-sound",
+    .qdev.size  = sizeof(sound_isabus_t),
+    .init       = pc98_sound_initfn,
+    .qdev.props = (Property[]) {
+        DEFINE_PROP_UINT32("irq", sound_isabus_t, isairq, 12),
+        DEFINE_PROP_END_OF_LIST(),
+    },
+};
+
+static void pc98_sound_register_devices(void)
+{
+    isa_qdev_register(&pc98_sound_info);
+}
+
+device_init(pc98_sound_register_devices)