Re: [PATCH v4 05/25] ppc/xive: Introduce a XiveFabric interface

[Cédric Le Goater]

On 03/10/2019 03:54, David Gibson wrote:
> On Wed, Sep 18, 2019 at 06:06:25PM +0200, Cédric Le Goater wrote:
>> The XiveFabric QOM interface should be implemented by the machine. It
>> acts as the PowerBUS interface between the interrupt controller and
>> the system. On HW, the XIVE sub-engine is responsible for the
>> communication with the other chip is the Common Queue (CQ) bridge
>> unit.
>>
>> This interface offers a 'match_nvt' handler to perform the CAM line
>> matching when looking for a XIVE Presenter with a dispatched NVT.
>>
>> Signed-off-by: Cédric Le Goater <address@hidden>
> 
> Um.. this has basically the same single method as the XivePresented
> interface you just introduced.  What's the distinction between them?

XivePresenter is the subengine of the controller, XiveFabric is the
bus linking the chips on the machine. PowerNV being multichip, when
looking for a target, we need to scan all presenters in the machine.

C. 

> 
>> ---
>>  include/hw/ppc/xive.h | 22 ++++++++++++++++++++++
>>  hw/intc/xive.c        | 10 ++++++++++
>>  2 files changed, 32 insertions(+)
>>
>> diff --git a/include/hw/ppc/xive.h b/include/hw/ppc/xive.h
>> index 39de45b87cb9..3c2910e10e25 100644
>> --- a/include/hw/ppc/xive.h
>> +++ b/include/hw/ppc/xive.h
>> @@ -399,6 +399,28 @@ int xive_presenter_tctx_match(XivePresenter *xptr, 
>> XiveTCTX *tctx,
>>                                uint8_t nvt_blk, uint32_t nvt_idx,
>>                                bool cam_ignore, uint32_t logic_serv);
>>  
>> +/*
>> + * XIVE Fabric (Interface between Interrupt Controller and Machine)
>> + */
>> +
>> +typedef struct XiveFabric XiveFabric;
>> +
>> +#define TYPE_XIVE_FABRIC "xive-fabric"
>> +#define XIVE_FABRIC(obj)                                     \
>> +    INTERFACE_CHECK(XiveFabric, (obj), TYPE_XIVE_FABRIC)
>> +#define XIVE_FABRIC_CLASS(klass)                                     \
>> +    OBJECT_CLASS_CHECK(XiveFabricClass, (klass), TYPE_XIVE_FABRIC)
>> +#define XIVE_FABRIC_GET_CLASS(obj)                                   \
>> +    OBJECT_GET_CLASS(XiveFabricClass, (obj), TYPE_XIVE_FABRIC)
>> +
>> +typedef struct XiveFabricClass {
>> +    InterfaceClass parent;
>> +    int (*match_nvt)(XiveFabric *xfb, uint8_t format,
>> +                     uint8_t nvt_blk, uint32_t nvt_idx,
>> +                     bool cam_ignore, uint8_t priority,
>> +                     uint32_t logic_serv, XiveTCTXMatch *match);
>> +} XiveFabricClass;
>> +
>>  /*
>>   * XIVE END ESBs
>>   */
>> diff --git a/hw/intc/xive.c b/hw/intc/xive.c
>> index fff50429f8ac..7a15a64ed7fe 100644
>> --- a/hw/intc/xive.c
>> +++ b/hw/intc/xive.c
>> @@ -1841,8 +1841,18 @@ static const TypeInfo xive_presenter_info = {
>>      .class_size = sizeof(XivePresenterClass),
>>  };
>>  
>> +/*
>> + * XIVE Fabric
>> + */
>> +static const TypeInfo xive_fabric_info = {
>> +    .name = TYPE_XIVE_FABRIC,
>> +    .parent = TYPE_INTERFACE,
>> +    .class_size = sizeof(XiveFabricClass),
>> +};
>> +
>>  static void xive_register_types(void)
>>  {
>> +    type_register_static(&xive_fabric_info);
>>      type_register_static(&xive_source_info);
>>      type_register_static(&xive_notifier_info);
>>      type_register_static(&xive_presenter_info);
>