Re: [Qemu-devel] [RFC] QOM design - add instance data to Object (-> add constructors)

[Liviu Ionescu]

> On 14 Jun 2015, at 15:43, Liviu Ionescu <address@hidden> wrote:
> 
> in practical terms this means that realize() should be called right after 
> creation, immediately after setting the properties:
> 
>   DeviceState *mcu = qdev_create(NULL, TYPE_STM32F103RB);
>   {
>       qdev_prop_set_uint32(mcu, "hse-freq-hz", 8000000); /* 8.0 MHz */
>       qdev_prop_set_uint32(mcu, "lse-freq-hz", 32768); /* 32 KHz */
>   }
>   qdev_realize(mcu);
> 
> which is ok as long as it is strictly adhered.

after adding aliases from the mcu to the internal rcc, I discovered that this 
is no longer true, if the object creation is done at realize(), the target 
object and the aliases do not exist before realize, so these settings are not 
possible.

so, from my point of view, this topic is clear now, realize() is not the right 
place for construction and the only viable solution is to use explicit 
constructors.

    DeviceState *mcu = qdev_alloc(NULL, TYPE_STM32F103RB);
    {
        STM32F103RB_GET_CLASS(mcu)->construct(OBJECT(mcu), machine);

        /* Set the board specific oscillator frequencies. */
        qdev_prop_set_uint32(mcu, "hse-freq-hz", 8000000); /* 8.0 MHz */
        qdev_prop_set_uint32(mcu, "lse-freq-hz", 32768); /* 32 KHz */
    }
    qdev_realize(mcu);


one less issue to worry about. :-)


regards,

Liviu