Re: [PATCH 4/4] xics: Merge TYPE_ICS_BASE and TYPE_ICS_SIMPLE classes

["Cédric Le Goater" <clg@kaod.org>]

On 25/09/2019 08:04, Cédric Le Goater wrote:
> On 25/09/2019 03:46, David Gibson wrote:
>> On Tue, Sep 24, 2019 at 04:06:02PM +0200, Cédric Le Goater wrote:
>>> On 24/09/2019 13:41, David Gibson wrote:
>>>> On Tue, Sep 24, 2019 at 07:31:44AM +0200, Cédric Le Goater wrote:
>>>>> On 24/09/2019 06:59, David Gibson wrote:
>>>>>> TYPE_ICS_SIMPLE is the only subtype of TYPE_ICS_BASE that's ever
>>>>>> instantiated, and the only one we're ever likely to want.  The
>>>>>> existence of different classes is just a hang over from when we
>>>>>> (misguidedly) had separate subtypes for the KVM and non-KVM version of
>>>>>> the device.
>>>>>>
>>>>>> So, collapse the two classes together into just TYPE_ICS.
>>>>>
>>>>>
>>>>> Well, I have been maintaining another subclass for the PHB3 MSI 
>>>>> but it has never been merged and it will require some rework.
>>>>
>>>> Well, if you did do this again, is there an actual need for it to be a
>>>> subclass of ICS_BASE, and not ICS_SIMPLE?  AFAICT the merged ICS class
>>>> should be fine for pnv as well.
>>>
>>> the reject resend handlers might be an issue. Anyhow, let's merge this 
>>> cleanup. PHB3 has been out of tree for too long.
>>
>> Hrm, are you sure.  I remember thinking the other day "whatever
>> happened to that PHB3 patchset?".  Is it actually broken,
> 
> It is not broken. 
> 
> PowerNV machines can boot rather complex PCI layouts on P8 (XICS) 
> and P9 (XIVE). See the complex configuration examples here :
> 
>   https://github.com/legoater/qemu/wiki/PowerNV
> 
>> or has it just been a long time since it was posted, and therefore 
>> been forgotten by me.
> 
> It hasn't been posted in a long time (+1 year). Here are the latest
> exchanges we had in November: 
> 
>   http://patchwork.ozlabs.org/patch/951227/
> 
> Nothing really worrying : 
> 
>   - some XICS infrastructure are needed (currently being removed)
>   - check if we need a separate source model for the MSI/LSI 
>   - rework the PBCQ modeling to some extent.
>   - misc cleanups.
> 
> I have been quite busy this last year. I would appreciate if someone 
> could take ownership of the PHB part. 


Recent XICS changes have made support of PHB3 complex and I don't have 
time to keep it alive anymore.

I am dropping the patch from my tree. In case someone wants to take 
over, it's here : 

    https://github.com/legoater/qemu/commits/powernv-4.2-p8

Focus is on P9 and P10 now.

Cheers,

C.