[PATCH v3 16/19] arm/arm64: KVM: add virtual GICv3 distributor emulation / PART 2

Andre Przywara andre.przywara at arm.com
Thu Nov 13 04:01:40 PST 2014


On 13/11/14 11:45, Marc Zyngier wrote:
> On 13/11/14 11:18, Christoffer Dall wrote:
>> On Wed, Nov 12, 2014 at 12:39:05PM +0000, Andre Przywara wrote:
>>> Hej Christoffer,
>>>
>>> the promised part 2 of the reply:
>>>
>>> On 07/11/14 14:30, Christoffer Dall wrote:
>>>> On Fri, Oct 31, 2014 at 05:26:51PM +0000, Andre Przywara wrote:
>>>>> With everything separated and prepared, we implement a model of a
>>>>> GICv3 distributor and redistributors by using the existing framework
>>>>> to provide handler functions for each register group.
>>>
>>> [...]
>>>
>>>>> +
>>>>> +static const struct mmio_range vgic_dist_ranges[] = {
>>>
>>> [...]
>>>
>>>>> +     /* the next three blocks are RES0 if ARE=1 */
>>>>
>>>> probably nicer to just have a comment for each register where this
>>>> applies.
>>>
>>> Done.
>>>
>>>>
>>>>> +     {
>>>>> +             .base           = GICD_SGIR,
>>>>> +             .len            = 4,
>>>>> +             .handle_mmio    = handle_mmio_raz_wi,
>>>>> +     },
>>>>> +     {
>>>>> +             .base           = GICD_CPENDSGIR,
>>>>> +             .len            = 0x10,
>>>>> +             .handle_mmio    = handle_mmio_raz_wi,
>>>>> +     },
>>>>> +     {
>>>>> +             .base           = GICD_SPENDSGIR,
>>>>> +             .len            = 0x10,
>>>>> +             .handle_mmio    = handle_mmio_raz_wi,
>>>>> +     },
>>>>> +     {
>>>>> +             .base           = GICD_IROUTER,
>>>>> +             .len            = 0x2000,
>>>>
>>>> shouldn't this be 0x1ee0?
>>>
>>> The limit of 0x7FD8 in the spec seems to come from 1020 - 32 SPIs.
>>> However all the other registers always claim 1024 IRQs supported (with
>>> non-implemented SPIs being RAZ/WI anyway).
>>> So I wonder if this is just a inconsistency in the spec.
>>> Marc, can you comment?
>>
>> The spec's memory map clearly indicates that the space at 0x6100 +
>> 0x1edc an onwards is reserverd, so it feels weird to define IROUTER
>> registers here.
>>
>> Indeed you guys should check what the true intention is.
> 
> Indeed, the spec is very clear about the range 0x7fdc-0xbffc to be
> reserved. Andre, can you please update this?

Ah, yes I skipped this, sorry. Will fix it.

Regards,
Andre.



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