Patchwork [01/14] lm32: add Milkymist AC97 support

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Submitter Michael Walle
Date March 7, 2011, 10:32 p.m.
Message ID <1299537165-16711-2-git-send-email-michael@walle.cc>
Download mbox | patch
Permalink /patch/85825/
State New
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Comments

Michael Walle - March 7, 2011, 10:32 p.m.
This patch adds support for the Milkymist AC97 compatible sound output and
input core.

Signed-off-by: Michael Walle <michael@walle.cc>
---
 Makefile.target     |    1 +
 configure           |    3 +
 hw/milkymist-ac97.c |  335 +++++++++++++++++++++++++++++++++++++++++++++++++++
 trace-events        |   12 ++
 4 files changed, 351 insertions(+), 0 deletions(-)
 create mode 100644 hw/milkymist-ac97.c
Alexander Graf - March 16, 2011, 4:50 p.m.
On 03/07/2011 11:32 PM, Michael Walle wrote:
> This patch adds support for the Milkymist AC97 compatible sound output and
> input core.

Malc, could you please take a look at this? :)

> Signed-off-by: Michael Walle<michael@walle.cc>
> ---
>   Makefile.target     |    1 +
>   configure           |    3 +
>   hw/milkymist-ac97.c |  335 +++++++++++++++++++++++++++++++++++++++++++++++++++
>   trace-events        |   12 ++
>   4 files changed, 351 insertions(+), 0 deletions(-)
>   create mode 100644 hw/milkymist-ac97.c
>
> diff --git a/Makefile.target b/Makefile.target
> index f0df98e..3be7868 100644
> --- a/Makefile.target
> +++ b/Makefile.target
> @@ -256,6 +256,7 @@ obj-lm32-y += lm32_juart.o
>   obj-lm32-y += lm32_timer.o
>   obj-lm32-y += lm32_uart.o
>   obj-lm32-y += lm32_sys.o
> +obj-lm32-y += milkymist-ac97.o
>
>   obj-mips-y = mips_r4k.o mips_jazz.o mips_malta.o mips_mipssim.o
>   obj-mips-y += mips_addr.o mips_timer.o mips_int.o
> diff --git a/configure b/configure
> index 5513d3e..e75e1a2 100755
> --- a/configure
> +++ b/configure
> @@ -3281,6 +3281,9 @@ if test "$target_softmmu" = "yes" ; then
>     arm)
>       cflags="-DHAS_AUDIO $cflags"
>     ;;
> +  lm32)
> +    cflags="-DHAS_AUDIO $cflags"
> +  ;;
>     i386|mips|ppc)
>       cflags="-DHAS_AUDIO -DHAS_AUDIO_CHOICE $cflags"
>     ;;
> diff --git a/hw/milkymist-ac97.c b/hw/milkymist-ac97.c
> new file mode 100644
> index 0000000..6c9e318
> --- /dev/null
> +++ b/hw/milkymist-ac97.c
> @@ -0,0 +1,335 @@
> +/*
> + *  QEMU model of the Milkymist System Controller.
> + *
> + *  Copyright (c) 2010 Michael Walle<michael@walle.cc>
> + *
> + * This library is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU Lesser General Public
> + * License as published by the Free Software Foundation; either
> + * version 2 of the License, or (at your option) any later version.
> + *
> + * This library is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + * Lesser General Public License for more details.
> + *
> + * You should have received a copy of the GNU Lesser General Public
> + * License along with this library; if not, see<http://www.gnu.org/licenses/>.
> + *
> + *
> + * Specification available at:
> + *   http://www.milkymist.org/socdoc/ac97.pdf
> + */
> +
> +#include "hw.h"
> +#include "sysbus.h"
> +#include "trace.h"
> +#include "audio/audio.h"
> +#include "qemu-error.h"
> +
> +enum {
> +    R_AC97_CTRL = 0,
> +    R_AC97_ADDR,
> +    R_AC97_DATAOUT,
> +    R_AC97_DATAIN,
> +    R_D_CTRL,
> +    R_D_ADDR,
> +    R_D_REMAINING,
> +    R_RESERVED,
> +    R_U_CTRL,
> +    R_U_ADDR,
> +    R_U_REMAINING,
> +    R_MAX
> +};
> +
> +enum {
> +    AC97_CTRL_RQEN  = (1<<0),
> +    AC97_CTRL_WRITE = (1<<1),
> +};
> +
> +enum {
> +    CTRL_EN = (1<<0),
> +};
> +
> +struct MilkymistAC97State {
> +    SysBusDevice busdev;
> +
> +    QEMUSoundCard card;
> +    SWVoiceIn *voice_in;
> +    SWVoiceOut *voice_out;
> +
> +    uint32_t regs[R_MAX];
> +
> +    qemu_irq crrequest_irq;
> +    qemu_irq crreply_irq;
> +    qemu_irq dmar_irq;
> +    qemu_irq dmaw_irq;
> +};
> +typedef struct MilkymistAC97State MilkymistAC97State;
> +
> +static void update_voices(MilkymistAC97State *s)
> +{
> +    if (s->regs[R_D_CTRL]&  CTRL_EN) {
> +        AUD_set_active_out(s->voice_out, 1);
> +    } else {
> +        AUD_set_active_out(s->voice_out, 0);
> +    }
> +
> +    if (s->regs[R_U_CTRL]&  CTRL_EN) {
> +        AUD_set_active_in(s->voice_in, 1);
> +    } else {
> +        AUD_set_active_in(s->voice_in, 0);
> +    }
> +}
> +
> +static uint32_t ac97_read(void *opaque, target_phys_addr_t addr)
> +{
> +    MilkymistAC97State *s = opaque;
> +    uint32_t r = 0;
> +
> +    addr>>= 2;
> +    switch (addr) {
> +    case R_AC97_CTRL:
> +    case R_AC97_ADDR:
> +    case R_AC97_DATAOUT:
> +    case R_AC97_DATAIN:
> +    case R_D_CTRL:
> +    case R_D_ADDR:
> +    case R_D_REMAINING:
> +    case R_U_CTRL:
> +    case R_U_ADDR:
> +    case R_U_REMAINING:
> +        r = s->regs[addr];
> +        break;
> +
> +    default:
> +        error_report("milkymist_ac97: read access to unkown register 0x"
> +                TARGET_FMT_plx, addr<<  2);
> +        break;
> +    }
> +
> +    trace_milkymist_ac97_memory_read(addr<<  2, r);
> +
> +    return r;
> +}
> +
> +static void ac97_write(void *opaque, target_phys_addr_t addr, uint32_t value)
> +{
> +    MilkymistAC97State *s = opaque;
> +
> +    trace_milkymist_ac97_memory_write(addr, value);
> +
> +    addr>>= 2;
> +    switch (addr) {
> +    case R_AC97_CTRL:
> +        /* always raise an IRQ according to the direction */
> +        if (value&  AC97_CTRL_RQEN) {
> +            if (value&  AC97_CTRL_WRITE) {
> +                trace_milkymist_ac97_pulse_irq_crrequest();
> +                qemu_irq_pulse(s->crrequest_irq);
> +            } else {
> +                trace_milkymist_ac97_pulse_irq_crreply();
> +                qemu_irq_pulse(s->crreply_irq);
> +            }
> +        }
> +
> +        /* RQEN is self clearing */
> +        s->regs[addr] = value&  ~AC97_CTRL_RQEN;
> +        break;
> +    case R_D_CTRL:
> +    case R_U_CTRL:
> +        s->regs[addr] = value;
> +        update_voices(s);
> +        break;
> +    case R_AC97_ADDR:
> +    case R_AC97_DATAOUT:
> +    case R_AC97_DATAIN:
> +    case R_D_ADDR:
> +    case R_D_REMAINING:
> +    case R_U_ADDR:
> +    case R_U_REMAINING:
> +        s->regs[addr] = value;
> +        break;
> +
> +    default:
> +        error_report("milkymist_ac97: write access to unkown register 0x"
> +                TARGET_FMT_plx, addr);
> +        break;
> +    }
> +
> +}
> +
> +static CPUReadMemoryFunc * const ac97_read_fn[] = {
> +    NULL,
> +    NULL,
> +&ac97_read,
> +};
> +
> +static CPUWriteMemoryFunc * const ac97_write_fn[] = {
> +    NULL,
> +    NULL,
> +&ac97_write,
> +};
> +
> +static void ac97_in_cb(void *opaque, int avail_b)
> +{
> +    MilkymistAC97State *s = opaque;
> +    uint8_t buf[4096];
> +    uint32_t remaining = s->regs[R_U_REMAINING];
> +    int temp = audio_MIN(remaining, avail_b);
> +    uint32_t addr = s->regs[R_U_ADDR];
> +    int transferred = 0;
> +
> +    trace_milkymist_ac97_in_cb(avail_b, remaining);
> +
> +    /* prevent from raising an IRQ */
> +    if (temp == 0) {
> +        return;
> +    }
> +
> +    while (temp) {
> +        int acquired, to_copy;
> +
> +        to_copy = audio_MIN(temp, sizeof(buf));
> +        acquired = AUD_read(s->voice_in, buf, to_copy);
> +        if (!acquired) {
> +            break;
> +        }
> +
> +        cpu_physical_memory_write(addr, buf, acquired);
> +
> +        temp -= acquired;
> +        addr += acquired;
> +        transferred += acquired;
> +    }
> +
> +    trace_milkymist_ac97_in_cb_transferred(transferred);
> +
> +    s->regs[R_U_ADDR] = addr;
> +    s->regs[R_U_REMAINING] -= transferred;
> +
> +    if ((s->regs[R_U_CTRL]&  CTRL_EN)&&  (s->regs[R_U_REMAINING] == 0)) {
> +        trace_milkymist_ac97_pulse_irq_dmaw();
> +        qemu_irq_pulse(s->dmaw_irq);
> +    }
> +}
> +
> +static void ac97_out_cb(void *opaque, int free_b)
> +{
> +    MilkymistAC97State *s = opaque;
> +    uint8_t buf[4096];
> +    uint32_t remaining = s->regs[R_D_REMAINING];
> +    int temp = audio_MIN(remaining, free_b);
> +    uint32_t addr = s->regs[R_D_ADDR];
> +    int transferred = 0;
> +
> +    trace_milkymist_ac97_out_cb(free_b, remaining);
> +
> +    /* prevent from raising an IRQ */
> +    if (temp == 0) {
> +        return;
> +    }
> +
> +    while (temp) {
> +        int copied, to_copy;
> +
> +        to_copy = audio_MIN(temp, sizeof(buf));
> +        cpu_physical_memory_read(addr, buf, to_copy);
> +        copied = AUD_write(s->voice_out, buf, to_copy);
> +        if (!copied) {
> +            break;
> +        }
> +        temp -= copied;
> +        addr += copied;
> +        transferred += copied;
> +    }
> +
> +    trace_milkymist_ac97_out_cb_transferred(transferred);
> +
> +    s->regs[R_D_ADDR] = addr;
> +    s->regs[R_D_REMAINING] -= transferred;
> +
> +    if ((s->regs[R_D_CTRL]&  CTRL_EN)&&  (s->regs[R_D_REMAINING] == 0)) {
> +        trace_milkymist_ac97_pulse_irq_dmar();
> +        qemu_irq_pulse(s->dmar_irq);
> +    }
> +}
> +
> +static void milkymist_ac97_reset(DeviceState *d)
> +{
> +    MilkymistAC97State *s = container_of(d, MilkymistAC97State, busdev.qdev);
> +    int i;
> +
> +    for (i = 0; i<  R_MAX; i++) {
> +        s->regs[i] = 0;
> +    }
> +
> +    AUD_set_active_in(s->voice_in, 0);
> +    AUD_set_active_out(s->voice_out, 0);
> +}
> +
> +static int ac97_post_load(void *opaque, int version_id)
> +{
> +    MilkymistAC97State *s = opaque;
> +
> +    update_voices(s);
> +
> +    return 0;
> +}
> +
> +static int milkymist_ac97_init(SysBusDevice *dev)
> +{
> +    MilkymistAC97State *s = FROM_SYSBUS(typeof(*s), dev);
> +    int ac97_regs;
> +
> +    struct audsettings as;
> +    sysbus_init_irq(dev,&s->crrequest_irq);
> +    sysbus_init_irq(dev,&s->crreply_irq);
> +    sysbus_init_irq(dev,&s->dmar_irq);
> +    sysbus_init_irq(dev,&s->dmaw_irq);
> +
> +    AUD_register_card("Milkymist AC'97",&s->card);
> +
> +    as.freq = 48000;
> +    as.nchannels = 2;
> +    as.fmt = AUD_FMT_S16;
> +    as.endianness = 1;
> +
> +    s->voice_in = AUD_open_in(&s->card, s->voice_in,
> +            "mm_ac97.in", s, ac97_in_cb,&as);
> +    s->voice_out = AUD_open_out(&s->card, s->voice_out,
> +            "mm_ac97.out", s, ac97_out_cb,&as);
> +
> +    ac97_regs = cpu_register_io_memory(ac97_read_fn, ac97_write_fn, s,
> +            DEVICE_NATIVE_ENDIAN);
> +    sysbus_init_mmio(dev, R_MAX * 4, ac97_regs);
> +
> +    return 0;
> +}
> +
> +static const VMStateDescription vmstate_milkymist_ac97 = {
> +    .name = "milkymist-ac97",
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .minimum_version_id_old = 1,
> +    .post_load = ac97_post_load,
> +    .fields      = (VMStateField[]) {
> +        VMSTATE_UINT32_ARRAY(regs, MilkymistAC97State, R_MAX),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +static SysBusDeviceInfo milkymist_ac97_info = {
> +    .init = milkymist_ac97_init,
> +    .qdev.name  = "milkymist-ac97",
> +    .qdev.size  = sizeof(MilkymistAC97State),
> +    .qdev.vmsd  =&vmstate_milkymist_ac97,
> +    .qdev.reset = milkymist_ac97_reset,
> +};
> +
> +static void milkymist_ac97_register(void)
> +{
> +    sysbus_register_withprop(&milkymist_ac97_info);
> +}
> +
> +device_init(milkymist_ac97_register)
> diff --git a/trace-events b/trace-events
> index c791719..9241ac9 100644
> --- a/trace-events
> +++ b/trace-events
> @@ -283,3 +283,15 @@ disable lm32_uart_irq_state(int level) "irq state %d"
>
>   # hw/lm32_sys.c
>   disable lm32_sys_memory_write(uint32_t addr, uint32_t value) "addr 0x%08x value 0x%08x"
> +
> +# hw/milkymist-ac97.c
> +disable milkymist_ac97_memory_read(uint32_t addr, uint32_t value) "addr %08x value %08x"
> +disable milkymist_ac97_memory_write(uint32_t addr, uint32_t value) "addr %08x value %08x"
> +disable milkymist_ac97_pulse_irq_crrequest(void) "Pulse IRQ CR request"
> +disable milkymist_ac97_pulse_irq_crreply(void) "Pulse IRQ CR reply"
> +disable milkymist_ac97_pulse_irq_dmaw(void) "Pulse IRQ DMA write"
> +disable milkymist_ac97_pulse_irq_dmar(void) "Pulse IRQ DMA read"
> +disable milkymist_ac97_in_cb(int avail, uint32_t remaining) "avail %d remaining %u"
> +disable milkymist_ac97_in_cb_transferred(int transferred) "transferred %d"
> +disable milkymist_ac97_out_cb(int free, uint32_t remaining) "free %d remaining %u"
> +disable milkymist_ac97_out_cb_transferred(int transferred) "transferred %d"
malc - March 16, 2011, 6:12 p.m.
On Wed, 16 Mar 2011, Alexander Graf wrote:

> On 03/07/2011 11:32 PM, Michael Walle wrote:
> > This patch adds support for the Milkymist AC97 compatible sound output and
> > input core.
> 
> Malc, could you please take a look at this? :)

Okay...

> 
> > Signed-off-by: Michael Walle<michael@walle.cc>
> > ---
> >   Makefile.target     |    1 +
> >   configure           |    3 +
> >   hw/milkymist-ac97.c |  335
> > +++++++++++++++++++++++++++++++++++++++++++++++++++
> >   trace-events        |   12 ++
> >   4 files changed, 351 insertions(+), 0 deletions(-)
> >   create mode 100644 hw/milkymist-ac97.c
> > 
> > diff --git a/Makefile.target b/Makefile.target
> > index f0df98e..3be7868 100644
> > --- a/Makefile.target
> > +++ b/Makefile.target
> > @@ -256,6 +256,7 @@ obj-lm32-y += lm32_juart.o
> >   obj-lm32-y += lm32_timer.o
> >   obj-lm32-y += lm32_uart.o
> >   obj-lm32-y += lm32_sys.o
> > +obj-lm32-y += milkymist-ac97.o
> > 
> >   obj-mips-y = mips_r4k.o mips_jazz.o mips_malta.o mips_mipssim.o
> >   obj-mips-y += mips_addr.o mips_timer.o mips_int.o
> > diff --git a/configure b/configure
> > index 5513d3e..e75e1a2 100755
> > --- a/configure
> > +++ b/configure
> > @@ -3281,6 +3281,9 @@ if test "$target_softmmu" = "yes" ; then
> >     arm)
> >       cflags="-DHAS_AUDIO $cflags"
> >     ;;
> > +  lm32)
> > +    cflags="-DHAS_AUDIO $cflags"
> > +  ;;
> >     i386|mips|ppc)
> >       cflags="-DHAS_AUDIO -DHAS_AUDIO_CHOICE $cflags"
> >     ;;
> > diff --git a/hw/milkymist-ac97.c b/hw/milkymist-ac97.c
> > new file mode 100644
> > index 0000000..6c9e318
> > --- /dev/null
> > +++ b/hw/milkymist-ac97.c
> > @@ -0,0 +1,335 @@
> > +/*
> > + *  QEMU model of the Milkymist System Controller.
> > + *
> > + *  Copyright (c) 2010 Michael Walle<michael@walle.cc>
> > + *
> > + * This library is free software; you can redistribute it and/or
> > + * modify it under the terms of the GNU Lesser General Public
> > + * License as published by the Free Software Foundation; either
> > + * version 2 of the License, or (at your option) any later version.
> > + *
> > + * This library is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> > + * Lesser General Public License for more details.
> > + *
> > + * You should have received a copy of the GNU Lesser General Public
> > + * License along with this library; if not,
> > see<http://www.gnu.org/licenses/>.
> > + *
> > + *
> > + * Specification available at:
> > + *   http://www.milkymist.org/socdoc/ac97.pdf
> > + */
> > +
> > +#include "hw.h"
> > +#include "sysbus.h"
> > +#include "trace.h"
> > +#include "audio/audio.h"
> > +#include "qemu-error.h"
> > +
> > +enum {
> > +    R_AC97_CTRL = 0,

Unneeded..

> > +    R_AC97_ADDR,
> > +    R_AC97_DATAOUT,
> > +    R_AC97_DATAIN,
> > +    R_D_CTRL,
> > +    R_D_ADDR,
> > +    R_D_REMAINING,
> > +    R_RESERVED,
> > +    R_U_CTRL,
> > +    R_U_ADDR,
> > +    R_U_REMAINING,
> > +    R_MAX
> > +};
> > +
> > +enum {
> > +    AC97_CTRL_RQEN  = (1<<0),

Oookay..

> > +    AC97_CTRL_WRITE = (1<<1),

Incinsistent(with previous enum formatting) comma (and C99 only at that)

> > +};
> > +
> > +enum {
> > +    CTRL_EN = (1<<0),

Ditto x2

> > +};
> > +
> > +struct MilkymistAC97State {
> > +    SysBusDevice busdev;
> > +
> > +    QEMUSoundCard card;
> > +    SWVoiceIn *voice_in;
> > +    SWVoiceOut *voice_out;
> > +
> > +    uint32_t regs[R_MAX];
> > +
> > +    qemu_irq crrequest_irq;
> > +    qemu_irq crreply_irq;
> > +    qemu_irq dmar_irq;
> > +    qemu_irq dmaw_irq;
> > +};
> > +typedef struct MilkymistAC97State MilkymistAC97State;
> > +
> > +static void update_voices(MilkymistAC97State *s)
> > +{
> > +    if (s->regs[R_D_CTRL]&  CTRL_EN) {

Space before ampersand would be nice.

> > +        AUD_set_active_out(s->voice_out, 1);
> > +    } else {
> > +        AUD_set_active_out(s->voice_out, 0);
> > +    }
> > +
> > +    if (s->regs[R_U_CTRL]&  CTRL_EN) {
> > +        AUD_set_active_in(s->voice_in, 1);
> > +    } else {
> > +        AUD_set_active_in(s->voice_in, 0);
> > +    }
> > +}
> > +
> > +static uint32_t ac97_read(void *opaque, target_phys_addr_t addr)
> > +{
> > +    MilkymistAC97State *s = opaque;
> > +    uint32_t r = 0;
> > +
> > +    addr>>= 2;

Again space here and elsewhere.

> > +    switch (addr) {
> > +    case R_AC97_CTRL:
> > +    case R_AC97_ADDR:
> > +    case R_AC97_DATAOUT:
> > +    case R_AC97_DATAIN:
> > +    case R_D_CTRL:
> > +    case R_D_ADDR:
> > +    case R_D_REMAINING:
> > +    case R_U_CTRL:
> > +    case R_U_ADDR:
> > +    case R_U_REMAINING:
> > +        r = s->regs[addr];
> > +        break;
> > +
> > +    default:
> > +        error_report("milkymist_ac97: read access to unkown register 0x"
> > +                TARGET_FMT_plx, addr<<  2);
> > +        break;
> > +    }
> > +
> > +    trace_milkymist_ac97_memory_read(addr<<  2, r);
> > +
> > +    return r;
> > +}
> > +
> > +static void ac97_write(void *opaque, target_phys_addr_t addr, uint32_t
> > value)
> > +{
> > +    MilkymistAC97State *s = opaque;
> > +
> > +    trace_milkymist_ac97_memory_write(addr, value);
> > +
> > +    addr>>= 2;
> > +    switch (addr) {
> > +    case R_AC97_CTRL:
> > +        /* always raise an IRQ according to the direction */
> > +        if (value&  AC97_CTRL_RQEN) {
> > +            if (value&  AC97_CTRL_WRITE) {
> > +                trace_milkymist_ac97_pulse_irq_crrequest();
> > +                qemu_irq_pulse(s->crrequest_irq);
> > +            } else {
> > +                trace_milkymist_ac97_pulse_irq_crreply();
> > +                qemu_irq_pulse(s->crreply_irq);
> > +            }
> > +        }
> > +
> > +        /* RQEN is self clearing */
> > +        s->regs[addr] = value&  ~AC97_CTRL_RQEN;
> > +        break;
> > +    case R_D_CTRL:
> > +    case R_U_CTRL:
> > +        s->regs[addr] = value;
> > +        update_voices(s);
> > +        break;
> > +    case R_AC97_ADDR:
> > +    case R_AC97_DATAOUT:
> > +    case R_AC97_DATAIN:
> > +    case R_D_ADDR:
> > +    case R_D_REMAINING:
> > +    case R_U_ADDR:
> > +    case R_U_REMAINING:
> > +        s->regs[addr] = value;
> > +        break;
> > +
> > +    default:
> > +        error_report("milkymist_ac97: write access to unkown register 0x"
> > +                TARGET_FMT_plx, addr);
> > +        break;
> > +    }
> > +
> > +}
> > +
> > +static CPUReadMemoryFunc * const ac97_read_fn[] = {
> > +    NULL,
> > +    NULL,
> > +&ac97_read,
> > +};
> > +
> > +static CPUWriteMemoryFunc * const ac97_write_fn[] = {
> > +    NULL,
> > +    NULL,
> > +&ac97_write,
> > +};
> > +
> > +static void ac97_in_cb(void *opaque, int avail_b)
> > +{
> > +    MilkymistAC97State *s = opaque;
> > +    uint8_t buf[4096];
> > +    uint32_t remaining = s->regs[R_U_REMAINING];
> > +    int temp = audio_MIN(remaining, avail_b);
> > +    uint32_t addr = s->regs[R_U_ADDR];
> > +    int transferred = 0;
> > +
> > +    trace_milkymist_ac97_in_cb(avail_b, remaining);
> > +
> > +    /* prevent from raising an IRQ */
> > +    if (temp == 0) {
> > +        return;
> > +    }
> > +
> > +    while (temp) {
> > +        int acquired, to_copy;
> > +
> > +        to_copy = audio_MIN(temp, sizeof(buf));
> > +        acquired = AUD_read(s->voice_in, buf, to_copy);
> > +        if (!acquired) {
> > +            break;
> > +        }
> > +
> > +        cpu_physical_memory_write(addr, buf, acquired);
> > +
> > +        temp -= acquired;
> > +        addr += acquired;
> > +        transferred += acquired;
> > +    }
> > +
> > +    trace_milkymist_ac97_in_cb_transferred(transferred);
> > +
> > +    s->regs[R_U_ADDR] = addr;
> > +    s->regs[R_U_REMAINING] -= transferred;
> > +
> > +    if ((s->regs[R_U_CTRL]&  CTRL_EN)&&  (s->regs[R_U_REMAINING] == 0)) {
> > +        trace_milkymist_ac97_pulse_irq_dmaw();
> > +        qemu_irq_pulse(s->dmaw_irq);
> > +    }
> > +}
> > +
> > +static void ac97_out_cb(void *opaque, int free_b)
> > +{
> > +    MilkymistAC97State *s = opaque;
> > +    uint8_t buf[4096];
> > +    uint32_t remaining = s->regs[R_D_REMAINING];
> > +    int temp = audio_MIN(remaining, free_b);
> > +    uint32_t addr = s->regs[R_D_ADDR];
> > +    int transferred = 0;
> > +
> > +    trace_milkymist_ac97_out_cb(free_b, remaining);
> > +
> > +    /* prevent from raising an IRQ */
> > +    if (temp == 0) {
> > +        return;
> > +    }
> > +
> > +    while (temp) {
> > +        int copied, to_copy;
> > +
> > +        to_copy = audio_MIN(temp, sizeof(buf));
> > +        cpu_physical_memory_read(addr, buf, to_copy);
> > +        copied = AUD_write(s->voice_out, buf, to_copy);
> > +        if (!copied) {
> > +            break;
> > +        }
> > +        temp -= copied;
> > +        addr += copied;
> > +        transferred += copied;
> > +    }
> > +
> > +    trace_milkymist_ac97_out_cb_transferred(transferred);
> > +
> > +    s->regs[R_D_ADDR] = addr;
> > +    s->regs[R_D_REMAINING] -= transferred;
> > +
> > +    if ((s->regs[R_D_CTRL]&  CTRL_EN)&&  (s->regs[R_D_REMAINING] == 0)) {
> > +        trace_milkymist_ac97_pulse_irq_dmar();
> > +        qemu_irq_pulse(s->dmar_irq);
> > +    }
> > +}
> > +
> > +static void milkymist_ac97_reset(DeviceState *d)
> > +{
> > +    MilkymistAC97State *s = container_of(d, MilkymistAC97State,
> > busdev.qdev);
> > +    int i;
> > +
> > +    for (i = 0; i<  R_MAX; i++) {
> > +        s->regs[i] = 0;
> > +    }
> > +
> > +    AUD_set_active_in(s->voice_in, 0);
> > +    AUD_set_active_out(s->voice_out, 0);
> > +}
> > +
> > +static int ac97_post_load(void *opaque, int version_id)
> > +{
> > +    MilkymistAC97State *s = opaque;
> > +
> > +    update_voices(s);
> > +
> > +    return 0;
> > +}
> > +
> > +static int milkymist_ac97_init(SysBusDevice *dev)
> > +{
> > +    MilkymistAC97State *s = FROM_SYSBUS(typeof(*s), dev);
> > +    int ac97_regs;
> > +
> > +    struct audsettings as;
> > +    sysbus_init_irq(dev,&s->crrequest_irq);
> > +    sysbus_init_irq(dev,&s->crreply_irq);
> > +    sysbus_init_irq(dev,&s->dmar_irq);
> > +    sysbus_init_irq(dev,&s->dmaw_irq);
> > +
> > +    AUD_register_card("Milkymist AC'97",&s->card);
> > +
> > +    as.freq = 48000;
> > +    as.nchannels = 2;
> > +    as.fmt = AUD_FMT_S16;
> > +    as.endianness = 1;
> > +
> > +    s->voice_in = AUD_open_in(&s->card, s->voice_in,
> > +            "mm_ac97.in", s, ac97_in_cb,&as);
> > +    s->voice_out = AUD_open_out(&s->card, s->voice_out,
> > +            "mm_ac97.out", s, ac97_out_cb,&as);
> > +
> > +    ac97_regs = cpu_register_io_memory(ac97_read_fn, ac97_write_fn, s,
> > +            DEVICE_NATIVE_ENDIAN);
> > +    sysbus_init_mmio(dev, R_MAX * 4, ac97_regs);
> > +
> > +    return 0;
> > +}
> > +
> > +static const VMStateDescription vmstate_milkymist_ac97 = {
> > +    .name = "milkymist-ac97",
> > +    .version_id = 1,
> > +    .minimum_version_id = 1,
> > +    .minimum_version_id_old = 1,
> > +    .post_load = ac97_post_load,
> > +    .fields      = (VMStateField[]) {
> > +        VMSTATE_UINT32_ARRAY(regs, MilkymistAC97State, R_MAX),
> > +        VMSTATE_END_OF_LIST()
> > +    }
> > +};
> > +
> > +static SysBusDeviceInfo milkymist_ac97_info = {
> > +    .init = milkymist_ac97_init,
> > +    .qdev.name  = "milkymist-ac97",
> > +    .qdev.size  = sizeof(MilkymistAC97State),
> > +    .qdev.vmsd  =&vmstate_milkymist_ac97,
> > +    .qdev.reset = milkymist_ac97_reset,
> > +};
> > +
> > +static void milkymist_ac97_register(void)
> > +{
> > +    sysbus_register_withprop(&milkymist_ac97_info);
> > +}
> > +
> > +device_init(milkymist_ac97_register)
> > diff --git a/trace-events b/trace-events
> > index c791719..9241ac9 100644
> > --- a/trace-events
> > +++ b/trace-events
> > @@ -283,3 +283,15 @@ disable lm32_uart_irq_state(int level) "irq state %d"
> > 
> >   # hw/lm32_sys.c
> >   disable lm32_sys_memory_write(uint32_t addr, uint32_t value) "addr 0x%08x
> > value 0x%08x"
> > +
> > +# hw/milkymist-ac97.c
> > +disable milkymist_ac97_memory_read(uint32_t addr, uint32_t value) "addr
> > %08x value %08x"
> > +disable milkymist_ac97_memory_write(uint32_t addr, uint32_t value) "addr
> > %08x value %08x"
> > +disable milkymist_ac97_pulse_irq_crrequest(void) "Pulse IRQ CR request"
> > +disable milkymist_ac97_pulse_irq_crreply(void) "Pulse IRQ CR reply"
> > +disable milkymist_ac97_pulse_irq_dmaw(void) "Pulse IRQ DMA write"
> > +disable milkymist_ac97_pulse_irq_dmar(void) "Pulse IRQ DMA read"
> > +disable milkymist_ac97_in_cb(int avail, uint32_t remaining) "avail %d
> > remaining %u"
> > +disable milkymist_ac97_in_cb_transferred(int transferred) "transferred %d"
> > +disable milkymist_ac97_out_cb(int free, uint32_t remaining) "free %d
> > remaining %u"
> > +disable milkymist_ac97_out_cb_transferred(int transferred) "transferred %d"
> 

IOW looks good to me.
Michael Walle - March 16, 2011, 11:02 p.m.
Am Mittwoch 16 März 2011, 19:12:44 schrieb malc:
> > > diff --git a/hw/milkymist-ac97.c b/hw/milkymist-ac97.c
> > > new file mode 100644
> > > index 0000000..6c9e318
> > > --- /dev/null
> > > +++ b/hw/milkymist-ac97.c
> > > @@ -0,0 +1,335 @@
> > > +/*
> > > + *  QEMU model of the Milkymist System Controller.
> > > + *
> > > + *  Copyright (c) 2010 Michael Walle<michael@walle.cc>
> > > + *
> > > + * This library is free software; you can redistribute it and/or
> > > + * modify it under the terms of the GNU Lesser General Public
> > > + * License as published by the Free Software Foundation; either
> > > + * version 2 of the License, or (at your option) any later version.
> > > + *
> > > + * This library is distributed in the hope that it will be useful,
> > > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> > > + * Lesser General Public License for more details.
> > > + *
> > > + * You should have received a copy of the GNU Lesser General Public
> > > + * License along with this library; if not,
> > > see<http://www.gnu.org/licenses/>.
> > > + *
> > > + *
> > > + * Specification available at:
> > > + *   http://www.milkymist.org/socdoc/ac97.pdf
> > > + */
> > > +
> > > +#include "hw.h"
> > > +#include "sysbus.h"
> > > +#include "trace.h"
> > > +#include "audio/audio.h"
> > > +#include "qemu-error.h"
> > > +
> > > +enum {
> > > +    R_AC97_CTRL = 0,
> 
> Unneeded..
I wanted to point out, that the registers begin at offset 0. If i change this, 
i'll need to change all other models, too. Including the ones that have been 
committed.

> > > +    R_AC97_ADDR,
> > > +    R_AC97_DATAOUT,
> > > +    R_AC97_DATAIN,
> > > +    R_D_CTRL,
> > > +    R_D_ADDR,
> > > +    R_D_REMAINING,
> > > +    R_RESERVED,
> > > +    R_U_CTRL,
> > > +    R_U_ADDR,
> > > +    R_U_REMAINING,
> > > +    R_MAX
> > > +};
> > > +
> > > +enum {
> > > +    AC97_CTRL_RQEN  = (1<<0),
> 
> Oookay..
> 
> > > +    AC97_CTRL_WRITE = (1<<1),
> 
> Incinsistent(with previous enum formatting) comma (and C99 only at that)
> 
> > > +};
> > > +
> > > +enum {
> > > +    CTRL_EN = (1<<0),
> 
> Ditto x2
Ok, but it has a hidden agenda. R_MAX must always be the last entry, therefore 
i omitted the comma. Whereas the bit flags could still be extended. Again if 
this is a concern for you, i'll change that and all other models too.

> > > +};
> > > +
> > > +struct MilkymistAC97State {
> > > +    SysBusDevice busdev;
> > > +
> > > +    QEMUSoundCard card;
> > > +    SWVoiceIn *voice_in;
> > > +    SWVoiceOut *voice_out;
> > > +
> > > +    uint32_t regs[R_MAX];
> > > +
> > > +    qemu_irq crrequest_irq;
> > > +    qemu_irq crreply_irq;
> > > +    qemu_irq dmar_irq;
> > > +    qemu_irq dmaw_irq;
> > > +};
> > > +typedef struct MilkymistAC97State MilkymistAC97State;
> > > +
> > > +static void update_voices(MilkymistAC97State *s)
> > > +{
> > > +    if (s->regs[R_D_CTRL]&  CTRL_EN) {
> 
> Space before ampersand would be nice.
mh i think Alex email client messed this up. At least for me, there is one 
space before and one space after the ampersand in my original email.
Alexander Graf - March 16, 2011, 11:49 p.m.
On 17.03.2011, at 00:02, Michael Walle <michael@walle.cc> wrote:

> Am Mittwoch 16 März 2011, 19:12:44 schrieb malc:
>>>> diff --git a/hw/milkymist-ac97.c b/hw/milkymist-ac97.c
>>>> new file mode 100644
>>>> index 0000000..6c9e318
>>>> --- /dev/null
>>>> +++ b/hw/milkymist-ac97.c
>>>> @@ -0,0 +1,335 @@
>>>> +/*
>>>> + *  QEMU model of the Milkymist System Controller.
>>>> + *
>>>> + *  Copyright (c) 2010 Michael Walle<michael@walle.cc>
>>>> + *
>>>> + * This library is free software; you can redistribute it and/or
>>>> + * modify it under the terms of the GNU Lesser General Public
>>>> + * License as published by the Free Software Foundation; either
>>>> + * version 2 of the License, or (at your option) any later version.
>>>> + *
>>>> + * This library is distributed in the hope that it will be useful,
>>>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>>>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
>>>> + * Lesser General Public License for more details.
>>>> + *
>>>> + * You should have received a copy of the GNU Lesser General Public
>>>> + * License along with this library; if not,
>>>> see<http://www.gnu.org/licenses/>.
>>>> + *
>>>> + *
>>>> + * Specification available at:
>>>> + *   http://www.milkymist.org/socdoc/ac97.pdf
>>>> + */
>>>> +
>>>> +#include "hw.h"
>>>> +#include "sysbus.h"
>>>> +#include "trace.h"
>>>> +#include "audio/audio.h"
>>>> +#include "qemu-error.h"
>>>> +
>>>> +enum {
>>>> +    R_AC97_CTRL = 0,
>> 
>> Unneeded..
> I wanted to point out, that the registers begin at offset 0. If i change this, 
> i'll need to change all other models, too. Including the ones that have been 
> committed.
> 
>>>> +    R_AC97_ADDR,
>>>> +    R_AC97_DATAOUT,
>>>> +    R_AC97_DATAIN,
>>>> +    R_D_CTRL,
>>>> +    R_D_ADDR,
>>>> +    R_D_REMAINING,
>>>> +    R_RESERVED,
>>>> +    R_U_CTRL,
>>>> +    R_U_ADDR,
>>>> +    R_U_REMAINING,
>>>> +    R_MAX
>>>> +};
>>>> +
>>>> +enum {
>>>> +    AC97_CTRL_RQEN  = (1<<0),
>> 
>> Oookay..
>> 
>>>> +    AC97_CTRL_WRITE = (1<<1),
>> 
>> Incinsistent(with previous enum formatting) comma (and C99 only at that)
>> 
>>>> +};
>>>> +
>>>> +enum {
>>>> +    CTRL_EN = (1<<0),
>> 
>> Ditto x2
> Ok, but it has a hidden agenda. R_MAX must always be the last entry, therefore 
> i omitted the comma. Whereas the bit flags could still be extended. Again if 
> this is a concern for you, i'll change that and all other models too.
> 
>>>> +};
>>>> +
>>>> +struct MilkymistAC97State {
>>>> +    SysBusDevice busdev;
>>>> +
>>>> +    QEMUSoundCard card;
>>>> +    SWVoiceIn *voice_in;
>>>> +    SWVoiceOut *voice_out;
>>>> +
>>>> +    uint32_t regs[R_MAX];
>>>> +
>>>> +    qemu_irq crrequest_irq;
>>>> +    qemu_irq crreply_irq;
>>>> +    qemu_irq dmar_irq;
>>>> +    qemu_irq dmaw_irq;
>>>> +};
>>>> +typedef struct MilkymistAC97State MilkymistAC97State;
>>>> +
>>>> +static void update_voices(MilkymistAC97State *s)
>>>> +{
>>>> +    if (s->regs[R_D_CTRL]&  CTRL_EN) {
>> 
>> Space before ampersand would be nice.
> mh i think Alex email client messed this up. At least for me, there is one 
> space before and one space after the ampersand in my original email.

Yes, thunderbird breaks those. Sorry :).

Alex

> 
> -- 
> Michael
malc - March 17, 2011, 12:10 a.m.
On Thu, 17 Mar 2011, Michael Walle wrote:

> Am Mittwoch 16 M?rz 2011, 19:12:44 schrieb malc:
> > > > diff --git a/hw/milkymist-ac97.c b/hw/milkymist-ac97.c
> > > > new file mode 100644
> > > > index 0000000..6c9e318
> > > > --- /dev/null
> > > > +++ b/hw/milkymist-ac97.c
> > > > @@ -0,0 +1,335 @@
> > > > +/*
> > > > + *  QEMU model of the Milkymist System Controller.
> > > > + *
> > > > + *  Copyright (c) 2010 Michael Walle<michael@walle.cc>
> > > > + *
> > > > + * This library is free software; you can redistribute it and/or
> > > > + * modify it under the terms of the GNU Lesser General Public
> > > > + * License as published by the Free Software Foundation; either
> > > > + * version 2 of the License, or (at your option) any later version.
> > > > + *
> > > > + * This library is distributed in the hope that it will be useful,
> > > > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> > > > + * Lesser General Public License for more details.
> > > > + *
> > > > + * You should have received a copy of the GNU Lesser General Public
> > > > + * License along with this library; if not,
> > > > see<http://www.gnu.org/licenses/>.
> > > > + *
> > > > + *
> > > > + * Specification available at:
> > > > + *   http://www.milkymist.org/socdoc/ac97.pdf
> > > > + */
> > > > +
> > > > +#include "hw.h"
> > > > +#include "sysbus.h"
> > > > +#include "trace.h"
> > > > +#include "audio/audio.h"
> > > > +#include "qemu-error.h"
> > > > +
> > > > +enum {
> > > > +    R_AC97_CTRL = 0,
> > 
> > Unneeded..
> I wanted to point out, that the registers begin at offset 0. If i change 
> this, i'll need to change all other models, too. Including the ones that 
> have been committed.

And i just wanted to nitpick that it would be zero even without '= 0' part
(6.7.2.2#3 of ISO/IEC 9899:201x)

> 
> > > > +    R_AC97_ADDR,
> > > > +    R_AC97_DATAOUT,
> > > > +    R_AC97_DATAIN,
> > > > +    R_D_CTRL,
> > > > +    R_D_ADDR,
> > > > +    R_D_REMAINING,
> > > > +    R_RESERVED,
> > > > +    R_U_CTRL,
> > > > +    R_U_ADDR,
> > > > +    R_U_REMAINING,
> > > > +    R_MAX
> > > > +};
> > > > +
> > > > +enum {
> > > > +    AC97_CTRL_RQEN  = (1<<0),
> > 
> > Oookay..
> > 
> > > > +    AC97_CTRL_WRITE = (1<<1),
> > 
> > Incinsistent(with previous enum formatting) comma (and C99 only at that)
> > 
> > > > +};
> > > > +
> > > > +enum {
> > > > +    CTRL_EN = (1<<0),
> > 
> > Ditto x2
> Ok, but it has a hidden agenda. R_MAX must always be the last entry, therefore 
> i omitted the comma. Whereas the bit flags could still be extended. Again if 
> this is a concern for you, i'll change that and all other models too.
> 
> > > > +};
> > > > +
> > > > +struct MilkymistAC97State {
> > > > +    SysBusDevice busdev;
> > > > +
> > > > +    QEMUSoundCard card;
> > > > +    SWVoiceIn *voice_in;
> > > > +    SWVoiceOut *voice_out;
> > > > +
> > > > +    uint32_t regs[R_MAX];
> > > > +
> > > > +    qemu_irq crrequest_irq;
> > > > +    qemu_irq crreply_irq;
> > > > +    qemu_irq dmar_irq;
> > > > +    qemu_irq dmaw_irq;
> > > > +};
> > > > +typedef struct MilkymistAC97State MilkymistAC97State;
> > > > +
> > > > +static void update_voices(MilkymistAC97State *s)
> > > > +{
> > > > +    if (s->regs[R_D_CTRL]&  CTRL_EN) {
> > 
> > Space before ampersand would be nice.
> mh i think Alex email client messed this up. At least for me, there is one 
> space before and one space after the ampersand in my original email.
> 

Sorry for the noise then. (to Alexander: real men don't use crap MUA
you use)

Patch

diff --git a/Makefile.target b/Makefile.target
index f0df98e..3be7868 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -256,6 +256,7 @@  obj-lm32-y += lm32_juart.o
 obj-lm32-y += lm32_timer.o
 obj-lm32-y += lm32_uart.o
 obj-lm32-y += lm32_sys.o
+obj-lm32-y += milkymist-ac97.o
 
 obj-mips-y = mips_r4k.o mips_jazz.o mips_malta.o mips_mipssim.o
 obj-mips-y += mips_addr.o mips_timer.o mips_int.o
diff --git a/configure b/configure
index 5513d3e..e75e1a2 100755
--- a/configure
+++ b/configure
@@ -3281,6 +3281,9 @@  if test "$target_softmmu" = "yes" ; then
   arm)
     cflags="-DHAS_AUDIO $cflags"
   ;;
+  lm32)
+    cflags="-DHAS_AUDIO $cflags"
+  ;;
   i386|mips|ppc)
     cflags="-DHAS_AUDIO -DHAS_AUDIO_CHOICE $cflags"
   ;;
diff --git a/hw/milkymist-ac97.c b/hw/milkymist-ac97.c
new file mode 100644
index 0000000..6c9e318
--- /dev/null
+++ b/hw/milkymist-ac97.c
@@ -0,0 +1,335 @@ 
+/*
+ *  QEMU model of the Milkymist System Controller.
+ *
+ *  Copyright (c) 2010 Michael Walle <michael@walle.cc>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ *
+ *
+ * Specification available at:
+ *   http://www.milkymist.org/socdoc/ac97.pdf
+ */
+
+#include "hw.h"
+#include "sysbus.h"
+#include "trace.h"
+#include "audio/audio.h"
+#include "qemu-error.h"
+
+enum {
+    R_AC97_CTRL = 0,
+    R_AC97_ADDR,
+    R_AC97_DATAOUT,
+    R_AC97_DATAIN,
+    R_D_CTRL,
+    R_D_ADDR,
+    R_D_REMAINING,
+    R_RESERVED,
+    R_U_CTRL,
+    R_U_ADDR,
+    R_U_REMAINING,
+    R_MAX
+};
+
+enum {
+    AC97_CTRL_RQEN  = (1<<0),
+    AC97_CTRL_WRITE = (1<<1),
+};
+
+enum {
+    CTRL_EN = (1<<0),
+};
+
+struct MilkymistAC97State {
+    SysBusDevice busdev;
+
+    QEMUSoundCard card;
+    SWVoiceIn *voice_in;
+    SWVoiceOut *voice_out;
+
+    uint32_t regs[R_MAX];
+
+    qemu_irq crrequest_irq;
+    qemu_irq crreply_irq;
+    qemu_irq dmar_irq;
+    qemu_irq dmaw_irq;
+};
+typedef struct MilkymistAC97State MilkymistAC97State;
+
+static void update_voices(MilkymistAC97State *s)
+{
+    if (s->regs[R_D_CTRL] & CTRL_EN) {
+        AUD_set_active_out(s->voice_out, 1);
+    } else {
+        AUD_set_active_out(s->voice_out, 0);
+    }
+
+    if (s->regs[R_U_CTRL] & CTRL_EN) {
+        AUD_set_active_in(s->voice_in, 1);
+    } else {
+        AUD_set_active_in(s->voice_in, 0);
+    }
+}
+
+static uint32_t ac97_read(void *opaque, target_phys_addr_t addr)
+{
+    MilkymistAC97State *s = opaque;
+    uint32_t r = 0;
+
+    addr >>= 2;
+    switch (addr) {
+    case R_AC97_CTRL:
+    case R_AC97_ADDR:
+    case R_AC97_DATAOUT:
+    case R_AC97_DATAIN:
+    case R_D_CTRL:
+    case R_D_ADDR:
+    case R_D_REMAINING:
+    case R_U_CTRL:
+    case R_U_ADDR:
+    case R_U_REMAINING:
+        r = s->regs[addr];
+        break;
+
+    default:
+        error_report("milkymist_ac97: read access to unkown register 0x"
+                TARGET_FMT_plx, addr << 2);
+        break;
+    }
+
+    trace_milkymist_ac97_memory_read(addr << 2, r);
+
+    return r;
+}
+
+static void ac97_write(void *opaque, target_phys_addr_t addr, uint32_t value)
+{
+    MilkymistAC97State *s = opaque;
+
+    trace_milkymist_ac97_memory_write(addr, value);
+
+    addr >>= 2;
+    switch (addr) {
+    case R_AC97_CTRL:
+        /* always raise an IRQ according to the direction */
+        if (value & AC97_CTRL_RQEN) {
+            if (value & AC97_CTRL_WRITE) {
+                trace_milkymist_ac97_pulse_irq_crrequest();
+                qemu_irq_pulse(s->crrequest_irq);
+            } else {
+                trace_milkymist_ac97_pulse_irq_crreply();
+                qemu_irq_pulse(s->crreply_irq);
+            }
+        }
+
+        /* RQEN is self clearing */
+        s->regs[addr] = value & ~AC97_CTRL_RQEN;
+        break;
+    case R_D_CTRL:
+    case R_U_CTRL:
+        s->regs[addr] = value;
+        update_voices(s);
+        break;
+    case R_AC97_ADDR:
+    case R_AC97_DATAOUT:
+    case R_AC97_DATAIN:
+    case R_D_ADDR:
+    case R_D_REMAINING:
+    case R_U_ADDR:
+    case R_U_REMAINING:
+        s->regs[addr] = value;
+        break;
+
+    default:
+        error_report("milkymist_ac97: write access to unkown register 0x"
+                TARGET_FMT_plx, addr);
+        break;
+    }
+
+}
+
+static CPUReadMemoryFunc * const ac97_read_fn[] = {
+    NULL,
+    NULL,
+    &ac97_read,
+};
+
+static CPUWriteMemoryFunc * const ac97_write_fn[] = {
+    NULL,
+    NULL,
+    &ac97_write,
+};
+
+static void ac97_in_cb(void *opaque, int avail_b)
+{
+    MilkymistAC97State *s = opaque;
+    uint8_t buf[4096];
+    uint32_t remaining = s->regs[R_U_REMAINING];
+    int temp = audio_MIN(remaining, avail_b);
+    uint32_t addr = s->regs[R_U_ADDR];
+    int transferred = 0;
+
+    trace_milkymist_ac97_in_cb(avail_b, remaining);
+
+    /* prevent from raising an IRQ */
+    if (temp == 0) {
+        return;
+    }
+
+    while (temp) {
+        int acquired, to_copy;
+
+        to_copy = audio_MIN(temp, sizeof(buf));
+        acquired = AUD_read(s->voice_in, buf, to_copy);
+        if (!acquired) {
+            break;
+        }
+
+        cpu_physical_memory_write(addr, buf, acquired);
+
+        temp -= acquired;
+        addr += acquired;
+        transferred += acquired;
+    }
+
+    trace_milkymist_ac97_in_cb_transferred(transferred);
+
+    s->regs[R_U_ADDR] = addr;
+    s->regs[R_U_REMAINING] -= transferred;
+
+    if ((s->regs[R_U_CTRL] & CTRL_EN) && (s->regs[R_U_REMAINING] == 0)) {
+        trace_milkymist_ac97_pulse_irq_dmaw();
+        qemu_irq_pulse(s->dmaw_irq);
+    }
+}
+
+static void ac97_out_cb(void *opaque, int free_b)
+{
+    MilkymistAC97State *s = opaque;
+    uint8_t buf[4096];
+    uint32_t remaining = s->regs[R_D_REMAINING];
+    int temp = audio_MIN(remaining, free_b);
+    uint32_t addr = s->regs[R_D_ADDR];
+    int transferred = 0;
+
+    trace_milkymist_ac97_out_cb(free_b, remaining);
+
+    /* prevent from raising an IRQ */
+    if (temp == 0) {
+        return;
+    }
+
+    while (temp) {
+        int copied, to_copy;
+
+        to_copy = audio_MIN(temp, sizeof(buf));
+        cpu_physical_memory_read(addr, buf, to_copy);
+        copied = AUD_write(s->voice_out, buf, to_copy);
+        if (!copied) {
+            break;
+        }
+        temp -= copied;
+        addr += copied;
+        transferred += copied;
+    }
+
+    trace_milkymist_ac97_out_cb_transferred(transferred);
+
+    s->regs[R_D_ADDR] = addr;
+    s->regs[R_D_REMAINING] -= transferred;
+
+    if ((s->regs[R_D_CTRL] & CTRL_EN) && (s->regs[R_D_REMAINING] == 0)) {
+        trace_milkymist_ac97_pulse_irq_dmar();
+        qemu_irq_pulse(s->dmar_irq);
+    }
+}
+
+static void milkymist_ac97_reset(DeviceState *d)
+{
+    MilkymistAC97State *s = container_of(d, MilkymistAC97State, busdev.qdev);
+    int i;
+
+    for (i = 0; i < R_MAX; i++) {
+        s->regs[i] = 0;
+    }
+
+    AUD_set_active_in(s->voice_in, 0);
+    AUD_set_active_out(s->voice_out, 0);
+}
+
+static int ac97_post_load(void *opaque, int version_id)
+{
+    MilkymistAC97State *s = opaque;
+
+    update_voices(s);
+
+    return 0;
+}
+
+static int milkymist_ac97_init(SysBusDevice *dev)
+{
+    MilkymistAC97State *s = FROM_SYSBUS(typeof(*s), dev);
+    int ac97_regs;
+
+    struct audsettings as;
+    sysbus_init_irq(dev, &s->crrequest_irq);
+    sysbus_init_irq(dev, &s->crreply_irq);
+    sysbus_init_irq(dev, &s->dmar_irq);
+    sysbus_init_irq(dev, &s->dmaw_irq);
+
+    AUD_register_card("Milkymist AC'97", &s->card);
+
+    as.freq = 48000;
+    as.nchannels = 2;
+    as.fmt = AUD_FMT_S16;
+    as.endianness = 1;
+
+    s->voice_in = AUD_open_in(&s->card, s->voice_in,
+            "mm_ac97.in", s, ac97_in_cb, &as);
+    s->voice_out = AUD_open_out(&s->card, s->voice_out,
+            "mm_ac97.out", s, ac97_out_cb, &as);
+
+    ac97_regs = cpu_register_io_memory(ac97_read_fn, ac97_write_fn, s,
+            DEVICE_NATIVE_ENDIAN);
+    sysbus_init_mmio(dev, R_MAX * 4, ac97_regs);
+
+    return 0;
+}
+
+static const VMStateDescription vmstate_milkymist_ac97 = {
+    .name = "milkymist-ac97",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .minimum_version_id_old = 1,
+    .post_load = ac97_post_load,
+    .fields      = (VMStateField[]) {
+        VMSTATE_UINT32_ARRAY(regs, MilkymistAC97State, R_MAX),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static SysBusDeviceInfo milkymist_ac97_info = {
+    .init = milkymist_ac97_init,
+    .qdev.name  = "milkymist-ac97",
+    .qdev.size  = sizeof(MilkymistAC97State),
+    .qdev.vmsd  = &vmstate_milkymist_ac97,
+    .qdev.reset = milkymist_ac97_reset,
+};
+
+static void milkymist_ac97_register(void)
+{
+    sysbus_register_withprop(&milkymist_ac97_info);
+}
+
+device_init(milkymist_ac97_register)
diff --git a/trace-events b/trace-events
index c791719..9241ac9 100644
--- a/trace-events
+++ b/trace-events
@@ -283,3 +283,15 @@  disable lm32_uart_irq_state(int level) "irq state %d"
 
 # hw/lm32_sys.c
 disable lm32_sys_memory_write(uint32_t addr, uint32_t value) "addr 0x%08x value 0x%08x"
+
+# hw/milkymist-ac97.c
+disable milkymist_ac97_memory_read(uint32_t addr, uint32_t value) "addr %08x value %08x"
+disable milkymist_ac97_memory_write(uint32_t addr, uint32_t value) "addr %08x value %08x"
+disable milkymist_ac97_pulse_irq_crrequest(void) "Pulse IRQ CR request"
+disable milkymist_ac97_pulse_irq_crreply(void) "Pulse IRQ CR reply"
+disable milkymist_ac97_pulse_irq_dmaw(void) "Pulse IRQ DMA write"
+disable milkymist_ac97_pulse_irq_dmar(void) "Pulse IRQ DMA read"
+disable milkymist_ac97_in_cb(int avail, uint32_t remaining) "avail %d remaining %u"
+disable milkymist_ac97_in_cb_transferred(int transferred) "transferred %d"
+disable milkymist_ac97_out_cb(int free, uint32_t remaining) "free %d remaining %u"
+disable milkymist_ac97_out_cb_transferred(int transferred) "transferred %d"