Re: [Qemu-arm] [Qemu-devel] [PATCH v5 1/5] arm: qmp: add GICCapability struct

[Markus Armbruster <armbru@redhat.com>]

Markus Armbruster <armbru@redhat.com> writes:

> Peter Xu <peterx@redhat.com> writes:
>
>> Define new struct to describe whether we support specific GIC version.
>>
>> Signed-off-by: Peter Xu <peterx@redhat.com>
>> ---
>>  qapi-schema.json | 22 ++++++++++++++++++++++
>>  1 file changed, 22 insertions(+)
>>
>> diff --git a/qapi-schema.json b/qapi-schema.json
>> index f253a37..da9671a 100644
>> --- a/qapi-schema.json
>> +++ b/qapi-schema.json
>> @@ -4134,3 +4134,25 @@
>>  ##
>>  { 'enum': 'ReplayMode',
>>    'data': [ 'none', 'record', 'play' ] }
>> +
>> +##
>> +# @GICCapability:
>> +#
>> +# This struct describes capability for a specific GIC version. These
>> +# bits are not only decided by QEMU/KVM software version, but also
>> +# decided by the hardware that the program is running upon.
>> +#
>> +# @version:  version of GIC to be described.
>> +#
>> +# @emulated: whether current QEMU/hardware supports emulated GIC
>> +#            device in user space.
>> +#
>> +# @kernel:   whether current QEMU/hardware supports hardware
>> +#            accelerated GIC device in kernel.
>> +#
>> +# Since: 2.6
>> +##
>> +{ 'struct': 'GICCapability',
>> +  'data': { 'version': 'int',
>> +            'emulated': 'bool',
>> +            'kernel': 'bool' } }
>
> Are all four combinations of (emulated, kernel) possible?

Moreover, what do the combinations mean from a practical point of view?
What would a management application do with the information?