Re: [RFC 03/22] xen/arm: gic-v3: Fix the distributor region to 64kB

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

On 05/06/15 13:14, Ian Campbell wrote:
> On Fri, 2015-05-08 at 14:29 +0100, Julien Grall wrote:
>> On GICv3, the default size of the distributor region is 64kB. This
>> region can be extended
> 
> But never shrunk, correct? Would a sanity check during parsing be
> worthwhile?

Yes. See 5.3 in PRD03-GENC-010745 24.0. I can add a reference to it.

Well, we trust the device tree value in many place in Xen. If the DT
provided by the platform is wrong, Xen won't be the only software in
trouble.

>>  to provide an implementation defined set of
>> pages containing additional aliases for MSI. Although, the GICv3 driver
>> only access to register within the default distributor region.
> 
> "only accesses registers within".
> 
>>
>> Futhermore, our vGIC driver implementation don't support the extended
> 
> "Furthermore" and "doesn't support"
> 
>> distributor. Therefore there is no reason to claim it to DOM0.
> 
> I think I would say "expose" or "map" rather than claim?

I think "expose" is the best word as this region is trapped in Xen for
emulation.

>> Finally drop the field dbase_size which is not useful anymore.
>>
>> Signed-off-by: Julien Grall <julien.grall@citrix.com>
> 
> 
> With the typoes fixed:
> Acked-by: Ian Campbell <ian.campbell@citrix.com>

Thanks,

-- 
Julien Grall