Re: [Qemu-devel] IRQ number, interrupt number, interrupt line & GPIO[in/out]

[Peter Maydell]

On 2 March 2012 16:01, Anthony Liguori <address@hidden> wrote:
> On 03/02/2012 06:38 AM, Zhi Yong Wu wrote:
>> Can anyone explain their relationship and difference among them?  It
>> is very appreciated if you can make some comments. thanks.
>
>
> IRQ == interrupt.
>
> GPIO is just another name for an input or output pin on a chip which could
> be a IRQ line.

The other point to note here is that there are two different sets
of terminology:
(1) real world terminology, which is roughly what Anthony is describing
(2) QEMU qdev and sysbus terms, which don't necessarily always map
quite cleanly to (1)

In particular the QEMU type 'qemu_irq' is really just an arbitrary signal
(and would be better named GPIO) -- it is not always used for an
actual interrupt line.

-- PMM