Re: [Qemu-devel] [PATCH v2 7/9] PPC: e500: Support dynamically spawned sysbus devices

[Peter Crosthwaite <peter.crosthwaite@xilinx.com>]

On Thu, Jul 31, 2014 at 12:55 AM, Peter Maydell
<peter.maydell@linaro.org> wrote:
> On 2 July 2014 19:01, Alexander Graf <agraf@suse.de> wrote:
>> For e500 our approach to supporting dynamically spawned sysbus devices is to
>> create a simple bus from the guest's point of view within which we map those
>> devices dynamically.
>>
>> +    /* Connect sysbus device to virtual platform bus */
>> +    for (i = 0; i < sbdev->num_irq; i++) {
>> +        if (!sbdev->irqp[i]) {
>> +            /* This IRQ is an incoming IRQ, we can't wire those here */
>
> I don't understand this comment -- sysbus IRQs are all outbound
> by definition. Lines going in to a device are GPIOs. (Ideally we
> should get rid of "sysbus IRQs" completely and just use named
> inbound GPIOs for everything.)
>

I have some patches in this area. Will post shortly cc you and Alex.

> Also, sbdev->irqp[] is private to the sysbus implementation, so
> you shouldn't be fishing about in it in the platform code.
>

And this is in the crosshairs of that work:

@@ -47,8 +49,6 @@ struct SysBusDevice {
     /*< public >*/

     int num_irq;
-    qemu_irq irqs[QDEV_MAX_IRQ];
-    qemu_irq *irqp[QDEV_MAX_IRQ];


Regards,
Peter

> thanks
> -- PMM
>