Re: [Qemu-devel] [PATCH v4 5/9] ppc/xics: Use a helper to add a new ICS

[Cédric Le Goater]

On 09/22/2016 01:40 AM, David Gibson wrote:
> On Mon, Sep 19, 2016 at 11:59:33AM +0530, Nikunj A Dadhania wrote:
>> From: Benjamin Herrenschmidt <address@hidden>
>>
>> Signed-off-by: Benjamin Herrenschmidt <address@hidden>
>> [Move object allocation and adding child to the helper]
>> Signed-off-by: Nikunj A Dadhania <address@hidden>
>> Reviewed-by: David Gibson <address@hidden>
>> ---
>>  hw/intc/xics.c        | 10 ++++++++++
>>  hw/intc/xics_spapr.c  |  6 +-----
>>  include/hw/ppc/xics.h |  1 +
>>  3 files changed, 12 insertions(+), 5 deletions(-)
>>
>> diff --git a/hw/intc/xics.c b/hw/intc/xics.c
>> index 05e938f..c7901c4 100644
>> --- a/hw/intc/xics.c
>> +++ b/hw/intc/xics.c
>> @@ -109,6 +109,16 @@ static void xics_common_reset(DeviceState *d)
>>      }
>>  }
>>  
>> +void xics_add_ics(XICSState *xics)
>> +{
>> +    ICSState *ics;
>> +
>> +    ics = ICS(object_new(TYPE_ICS));
>> +    object_property_add_child(OBJECT(xics), "ics", OBJECT(ics), NULL);
> 
> You'll need to construct a name here so you don't have all the ics
> objects called an indistinguishable "ics".

Yes, exactly, and so PowerNV does not use it because at least three ics 
are needed : 

qemu) info qom-tree 
/machine (powernv-machine)
  /unattached (container)
    /sysbus (System)
    /ipmi-bt[0] (qemu:memory-region)
    /device[0] (pnv-phb3)
      /ics-phb-lsi (ics)
      /ics-phb-msi (phb3-msi)

      ...

      /psi (pnv-psi)
        /xscom-psi[0] (qemu:memory-region)
        /psihb[0] (qemu:memory-region)
        /ics-psi (ics)


I think we can drop that patch. 


However some routine like this one :

+void xics_insert_ics(XICSState *xics, ICSState *ics)
+{
+    ics->xics = xics;
+    QLIST_INSERT_HEAD(&xics->ics, ics, list);
+}
+

would be useful to hide the list details below xics : 


    /* link in the PSI ICS */
    xics_insert_ics(XICS_COMMON(&chip->xics), &chip->psi.ics);

    ....

    /* insert the ICS in XICS */
    xics_insert_ics(xics, phb->lsi_ics);
    xics_insert_ics(xics, ICS_BASE(phb->msis));


Cheers,

C. 

>> +    ics->xics = xics;
>> +    QLIST_INSERT_HEAD(&xics->ics, ics, list);
>> +}
>> +
>>  static void xics_prop_get_nr_irqs(Object *obj, Visitor *v, const char *name,
>>                                    void *opaque, Error **errp)
>>  {
>> diff --git a/hw/intc/xics_spapr.c b/hw/intc/xics_spapr.c
>> index 0b0845d..270f20e 100644
>> --- a/hw/intc/xics_spapr.c
>> +++ b/hw/intc/xics_spapr.c
>> @@ -305,12 +305,8 @@ static void xics_spapr_realize(DeviceState *dev, Error 
>> **errp)
>>  static void xics_spapr_initfn(Object *obj)
>>  {
>>      XICSState *xics = XICS_SPAPR(obj);
>> -    ICSState *ics;
>>  
>> -    ics = ICS(object_new(TYPE_ICS));
>> -    object_property_add_child(obj, "ics", OBJECT(ics), NULL);
>> -    ics->xics = xics;
>> -    QLIST_INSERT_HEAD(&xics->ics, ics, list);
>> +    xics_add_ics(xics);
>>  }
>>  
>>  static void xics_spapr_class_init(ObjectClass *oc, void *data)
>> diff --git a/include/hw/ppc/xics.h b/include/hw/ppc/xics.h
>> index e49a2da..a7a1e54 100644
>> --- a/include/hw/ppc/xics.h
>> +++ b/include/hw/ppc/xics.h
>> @@ -197,5 +197,6 @@ void ics_write_xive(ICSState *ics, int nr, int server,
>>  void ics_set_irq_type(ICSState *ics, int srcno, bool lsi);
>>  
>>  ICSState *xics_find_source(XICSState *icp, int irq);
>> +void xics_add_ics(XICSState *xics);
>>  
>>  #endif /* XICS_H */
>