Re: [PATCH v2 08/21] xen/arm: Initialize the virtual GIC later

[Julien Grall <julien.grall@linaro.org>]

Hi Ian,

On 09/09/14 06:33, Ian Campbell wrote:
> On Fri, 2014-08-29 at 16:04 -0400, Julien Grall wrote:
>>
>> On 29/08/14 15:49, Andrii Tseglytskyi wrote:
>>> On Fri, Aug 29, 2014 at 9:57 PM, Julien Grall <julien.grall@linaro.org> wrote:
>>>> You will have to modify the function for your purpose. If you plan to PIRQ
>>>> == VIRQ every time, you could do smth like:
>>>>
>>>>
>>>> d->arch.vgic.nr_spis = gic_number_lines() - 32;
>>>>
>>>> I assume, you already modified vgic_allocate_irq to return directly the
>>>> pirq, and do nothing in vgic_free_irq.
>>>
>>> Yes, locally I did the same as you mentioned, but I'm thinking about
>>> solution which will allow me to have 1 to 1 irq mapping and which will
>>> be acceptable for Xen mainline.
>>
>> IHMO, the best solution would adding a boolean in the new DOMCTL to
>> specify if we want to use PIRQ == VIRQ or not.
>
> Shouldn't it be up to the toolstack to pass in a suitably large nr_spis,
> i.e. at least as large as the maximum irq it wasn't to map 1:1?

For the moment, Xen always choose the VIRQ. Looking again to the 
hypercall, I think we can let the toolstack asking for a specific VIRQ.

For now, I don't handle this case. I will rework my series to do it. 
Hence, it will make patch #20 less uglier.

Also it would help Andrii use case and avoid him to carry a bigger patch :).

Regards,

-- 
Julien Grall