Re: [Qemu-devel] [PATCH v3 2/4] hw/char: QOM'ify etraxfs_ser.c

[Paolo Bonzini]

On 13/05/2016 05:07, xiaoqiang zhao wrote:
> * Drop the old SysBus init function and use instance_init
> * Call qemu_chr_add_handlers in the realize callback
> * Use qdev chardev prop instead of qemu_char_get_next_serial
> 
> Signed-off-by: xiaoqiang zhao <address@hidden>
> ---
>  hw/char/etraxfs_ser.c | 27 +++++++++++++++++----------
>  1 file changed, 17 insertions(+), 10 deletions(-)
> 
> diff --git a/hw/char/etraxfs_ser.c b/hw/char/etraxfs_ser.c
> index 146b387..6957c68 100644
> --- a/hw/char/etraxfs_ser.c
> +++ b/hw/char/etraxfs_ser.c
> @@ -159,6 +159,11 @@ static const MemoryRegionOps ser_ops = {
>      }
>  };
>  
> +static Property etraxfs_ser_properties[] = {
> +    DEFINE_PROP_CHR("etraxfs-serial", ETRAXSerial, chr),

The usual name for this property is "chardev".

> +    DEFINE_PROP_END_OF_LIST(),
> +};
> +
>  static void serial_receive(void *opaque, const uint8_t *buf, int size)
>  {
>      ETRAXSerial *s = opaque;
> @@ -209,40 +214,42 @@ static void etraxfs_ser_reset(DeviceState *d)
>  
>  }
>  
> -static int etraxfs_ser_init(SysBusDevice *dev)
> +static void etraxfs_ser_init(Object *obj)
>  {
> -    ETRAXSerial *s = ETRAX_SERIAL(dev);
> +    ETRAXSerial *s = ETRAX_SERIAL(obj);
> +    SysBusDevice *dev = SYS_BUS_DEVICE(obj);
>  
>      sysbus_init_irq(dev, &s->irq);
> -    memory_region_init_io(&s->mmio, OBJECT(s), &ser_ops, s,
> +    memory_region_init_io(&s->mmio, obj, &ser_ops, s,
>                            "etraxfs-serial", R_MAX * 4);
>      sysbus_init_mmio(dev, &s->mmio);
> +}
> +
> +static void etraxfs_ser_realize(DeviceState *dev, Error **errp)
> +{
> +    ETRAXSerial *s = ETRAX_SERIAL(dev);
>  
> -    /* FIXME use a qdev chardev prop instead of qemu_char_get_next_serial() 
> */
> -    s->chr = qemu_char_get_next_serial();
>      if (s->chr) {
>          qemu_chr_add_handlers(s->chr,
>                                serial_can_receive, serial_receive,
>                                serial_event, s);
>      }
> -    return 0;
>  }
>  
>  static void etraxfs_ser_class_init(ObjectClass *klass, void *data)
>  {
>      DeviceClass *dc = DEVICE_CLASS(klass);
> -    SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
>  
> -    k->init = etraxfs_ser_init;
>      dc->reset = etraxfs_ser_reset;
> -    /* Reason: init() method uses qemu_char_get_next_serial() */
> -    dc->cannot_instantiate_with_device_add_yet = true;
> +    dc->props = etraxfs_ser_properties;
> +    dc->realize = etraxfs_ser_realize;
>  }
>  
>  static const TypeInfo etraxfs_ser_info = {
>      .name          = TYPE_ETRAX_FS_SERIAL,
>      .parent        = TYPE_SYS_BUS_DEVICE,
>      .instance_size = sizeof(ETRAXSerial),
> +    .instance_init = etraxfs_ser_init,
>      .class_init    = etraxfs_ser_class_init,
>  };
>  
> 

I'm sorry, this is not enough.  You need to learn how to test this
device.  CRIS images are available at http://wiki.qemu.org/Testing.

You have not added a replacement for the call to
qemu_char_get_next_serial().  The board code in hw/cris/axis_dev88.c
needs to use qemu_char_get_next_serial().

I suggest creating a function like

    void etraxfs_ser_create(hwaddr addr, qemu_irq irq,
                            CharDriverState *chr) {
        DeviceState *dev;
        SysBusDevice *s;
        qemu_irq irq;

        dev = qdev_create(NULL, "extrafs,serial");
        s = SYS_BUS_DEVICE(dev);
        qdev_prop_set_chr(s, "chardev", chr);
        qdev_init_nofail(dev);
        sysbus_mmio_map(s, 0, addr);
        sysbus_connect_irq(s, 0, irq);
    }

and using it with qemu_char_get_next_serial() as the "chr" parameter.
Note that this code is untested.

Thanks,

Paolo