Re: [RFC PATCH-for-9.1? 1/2] target/arm: Move qmp_query_gic_capabilities() to hw/intc/

[Markus Armbruster]

Peter Maydell <peter.maydell@linaro.org> writes:

> On Thu, 8 Aug 2024 at 05:32, Markus Armbruster <armbru@redhat.com> wrote:
>>
>> Peter Maydell <peter.maydell@linaro.org> writes:
>>
>> [...]
>>
>> > The QAPI command which this code is implementing is
>> > also (a) target-specific and (b) unfortunately
>> > designed so that it doesn't get passed a particular
>> > CPU or particular device to query, it's just assumed
>> > to be a part of the whole simulation.
>>
>> We can fix (b) if we care: add a suitable optional argument, default to
>> the sole GIC in the system, fail if there's more than one.  I assume we
>> have no machines with more than one now.
>
> The exynos4210 SoC (board types 'nuri', 'smdkc210') has
> two GICs. (It's a rather odd design -- there's the
> interrupt controller that's part of the main CPU
> cluster, and then they used a second "external" GIC
> that feeds into that one.)

Then "fail if there's more than one" would be an incompatible change for
this machine.

If the two GICs have identical capabilities, it doesn't matter to which
of the two query-gic-capabilities technically applies.

Else, it matters, and we have an interface issue.  Do we?