Re: [Qemu-devel] [Qemu-ppc] [PATCH v2] spapr: populate ibm, loc-code

[Alexey Kardashevskiy <aik@ozlabs.ru>]

On 03/30/2015 04:34 PM, Nikunj A Dadhania wrote:
> Nikunj A Dadhania <nikunj@linux.vnet.ibm.com> writes:
>
>> David Gibson <david@gibson.dropbear.id.au> writes:
>>
>>> On Mon, Mar 30, 2015 at 01:18:01PM +1100, Alexey Kardashevskiy wrote:
>>>> On 03/27/2015 08:49 PM, Nikunj A Dadhania wrote:
>>>>> Each hardware instance has a platform unique location code.  The OF
>>>>> device tree that describes a part of a hardware entity must include
>>>>> the “ibm,loc-code” property with a value that represents the location
>>>>> code for that hardware entity.
>>>>>
>>>>> Introduce an hcall to populate ibm,loc-code.
>>>>> 1) PCI passthru devices need to identify with its own ibm,loc-code
>>>>>     available on the host.
>>>>> 2) Emulated devices encode as following: qemu_<name>:<slot>.<fn>
>>>>>
>>>>> Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
>>> [snip]
>>>>> diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
>>>>> index af71e8b..95157ac 100644
>>>>> --- a/include/hw/ppc/spapr.h
>>>>> +++ b/include/hw/ppc/spapr.h
>>>>> @@ -310,7 +310,10 @@ typedef struct sPAPREnvironment {
>>>>>   #define KVMPPC_H_LOGICAL_MEMOP  (KVMPPC_HCALL_BASE + 0x1)
>>>>>   /* Client Architecture support */
>>>>>   #define KVMPPC_H_CAS            (KVMPPC_HCALL_BASE + 0x2)
>>>>> -#define KVMPPC_HCALL_MAX        KVMPPC_H_CAS
>>>>> +#define KVMPPC_H_RTAS_UPDATE    (KVMPPC_HCALL_BASE + 0x3)
>>>>> +#define KVMPPC_H_REPORT_MC_ERR  (KVMPPC_HCALL_BASE + 0x4)
>>>>> +#define KVMPPC_H_GET_LOC_CODE   (KVMPPC_HCALL_BASE + 0x5)
>>>>> +#define KVMPPC_HCALL_MAX        KVMPPC_H_GET_LOC_CODE
>>>>
>>>>
>>>> Please add only relevant codes. And what happened to patches adding
>>>> H_RTAS_UPDATE and H_REPORT_MC_ERR?
>>>>
>>>> Also (it is probably a very stupid question but still :) ), why are all
>>>> these callbacks - hypercalls, not RTAS calls? The hypercalls are numbered in
>>>> sPAPR and we kind of stealing numbers from that space while we are
>>>> allocating RTAS tokens ourselves and have more freedom.
>>>
>>> Also, I thought the plan was to remove PCI device enumeration from
>>> SLOF and move it to qemu (since we need to partially do that for
>>> hotplug).
>>
>> For me it was a short term plan.
>
> Sorry, I meant PCI device enumeration removal from SLOF was a long term
> plan.


It does not have to be removal, rather adding a case if there are already 
devices present (or resources assigned) on a PHB in the device tree, then 
do not do scan, something like that.



>
>
>> IMHO, this cant be done in short time.
>>
>>> That removes the need for the hcall entirely.
>>>
>>> --
>>> David Gibson			| I'll have my music baroque, and my code
>>> david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
>>> 				| _way_ _around_!
>>> http://www.ozlabs.org/~dgibson
>


-- 
Alexey