Re: Request for New PPC Machine Supporting Multiple SMP Cores

["Cédric Le Goater" <clegoate@redhat.com>]

On 12/7/23 18:39, BALATON Zoltan wrote:
> On Thu, 7 Dec 2023, aziz tlili wrote:
>> Dear QEMU Team,
>>
>> I hope this message finds you well. I've been a user of QEMU for well over
>> a year.
>>
>> I wanted to share an idea for a potential enhancement that I believe could
>> benefit many users, including myself. It would be fantastic to have a new
>> PPC machine model similar to the existing mac99, but with support for
>> multiple SMP cores for both qemu-system-ppc and qemu-system-ppc64.
> 
> There are several machines in qemu-system-ppc64 that support SMP such as pseries and powernv I think. For qemu-system-ppc maybe only ppce500. The mac99 may create multiple CPUs (G4 when ron with qemu-system-ppc or G5 with qemu-system-ppc64) but not sure if there's an OS that can actually use that. Linux support for mac99 may not be the best.

64bit :

pseries machines support SMP and SMT
powernv machines support SMP, SMT and multisocket.
ppce500 machines (e6500 and e5500 CPUs) support SMP

32bit :

ppce500 machines (e500mc) have SMP support but there is an issue when
bringing up the secondaries.
It has never been done for the other machines AFAIK

Thanks,

C.

>> The ability to simulate multiple SMP cores within a PPC machine environment
>> would significantly enhance the capabilities of QEMU for various
>> applications, testing scenarios, and development purposes. This addition
>> could greatly benefit the community working on PowerPC architecture.
> 
> Sure. Contributions are welcome.
> 
>> I understand the complexities involved in such developments but wanted to
>> express the potential advantages and how this enhancement could contribute
>> to expanding QEMU's capabilities.
> 
> Problem is not in understanding the potential advantages but the lack of people interested in working on that so progress depends on somebody doing it and sending patches.
> 
> Regards,
> BALATON Zoltan
> 
>> Thank you for considering my suggestion. I would be more than happy to
>> provide further details or collaborate in any way that could assist in
>> making this idea a reality.
>>
>> Best regards,
>> Aziz Tlili
>>
>