Re: [PATCH v5 05/22] xen/arm: ITS: Port ITS driver to Xen

[Julien Grall <julien.grall@citrix.com>]

On 31/07/15 11:28, Vijay Kilari wrote:
> On Tue, Jul 28, 2015 at 10:16 PM, Julien Grall <julien.grall@citrix.com> wrote:
>> Hi Vijay,
>>
>> On 27/07/15 12:11, vijay.kilari@gmail.com wrote:
>>> From: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
>>>
>>> The linux driver is based on 4.1 with below commit id
>>>
>>> 3ad2a5f57656a14d964b673a5a0e4ab0e583c870
>>
>> This doesn't include commit 591e5bec13f15feb13fc445b6c9c59954711c4ac
>> "irqchip/gicv3-its: Fix mapping of LPIs to collections".
>>
>> On the version 4 of this series, Ian [1] said that it would be very nice
>> to have a similar approach in Xen. I would like to see it too.
> 
> By storing col_id in msi_desc as below, I am already taking care of
> the above commit
> in this series
> 
> struct msi_desc {
> #ifdef HAS_GICV3
>     unsigned int eventID;
>     struct its_device *dev;
>     u16 col_id;
> #endif
> };

Which requires the caller of the ITS command to explicitly pass the
collection ID...

It complicates the caller for nothing and requires you to have
explicitely irqdesc helpers.

Anyway, I don't see any reason to differ from Linux and AFAICT Ian was
also in favor of using the same approach as Linux (i.e the one in the
commit "irqchip/gicv3-its: Fix mapping of LPIs to collections").

Regards,

-- 
Julien Grall