On 04/27/2015 04:39 PM, Peter Crosthwaite wrote: > On Mon, Apr 27, 2015 at 6:37 AM, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote: >> >> >> On 27/04/2015 14:20, Eric Auger wrote: >>> On 04/27/2015 12:39 PM, Paolo Bonzini wrote: >>>> >>>> >>>> On 27/04/2015 10:26, Eric Auger wrote: >>>>>>> One of my long term goals is to try and get rid of sysbus IRQ >>>>>>> abstraction completely in favor of just qdev gpios. This means >>>>>>> features that apply to GPIOs automatically apply to IRQs and vice >>>>>>> versa. Can your notifier hook be pushed up to the qdev GPIO level to >>>>>>> make it more globally usable and avoid a new feature to sysbus IRQs? >>>>> Yes sure, I am going to put the notifier in DeviceClass then. >>>> >>>> I've thought too about this, and I'm not sure about it. >>>> >>>> It would mean you have to pass the gpio name (e.g. >>>> SYSBUS_DEVICE_GPIO_IRQ) to the hook, and in the case of sysbus IRQs this >>>> would leak the SYSBUS_DEVICE_GPIO_IRQ abstraction to the implementors of >>>> the hook. > > That's OK IMO. SYSBUS_DEVICE_GPIO_IRQ was never intended to be > private. The semantics of it are something like "If you don't have > anything better to name your IRQ pin use this". > > This adds the requirement on machine level code that you can't > consistently use sysbus_connect_irq for intc connection. But machines > should be able to connect any wires between any cores without having > to special case interrupts or chip-selects, resets or whatever. So the > name of the GPIO has to be exposed to the callback hook registration > if we want to break down this GPIO special casing. Names of interrupt > pins are system-level knowledge so I think this is all OK. > >>> Hi Paolo, >>> >>> Currently my notifier has the following proto: >>> void (*connect_gpio_out_notifier)(DeviceState *dev, qemu_irq irq); >>> >>> It is sufficient for my need. >>> >>> is it really mandated to pass other qdev_connect_gpio_out_named args, >>> ie. name & n? >> >> It's an ugly situation. If you look at qdev_connect_gpio_out_named, it >> is really a thin wrapper around object_property_set_link. Just like >> Peter wasn't too happy with changing sysbus_connect_irq, the same >> objection would apply here. Callers of object_property_set_link should >> call the notifiers, not just those that use qdev_connect_gpio_out_named. >> >> This is why I originally asked you to look into using the check callback >> instead. >> > > Is this still feasible? Pushing it up to the higher again to the QOM > level? I think this would be an ideal backend to the problem even if > we still go with a code-friendly sysbus frontend. Peter, Paolo, After your feedbacks, I feel I need to spend some more time on the original check() track. I would prefer not to introduce any patch that will make issue in the future. Thanks Eric > > Regards, > Peter > >> This is why I think it's better to keep the sysbus patch. >> >> Paolo >> _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
