Subject: [PATCH 2/3] KVM: arm/arm64: Add ARM arch timer interrupts ABI

From: [email-masked] (Marc Zyngier)
Date: Tue, 01 Nov 2016 16:56:47 +0000

On Tue, Nov 01 2016 at 02:54:11 PM, Peter Maydell <[email-masked]> wrote:
> On 1 November 2016 at 14:50, Christoffer Dall
> <[email-masked]> wrote:
>> On Tue, Nov 01, 2016 at 11:26:54AM +0000, Peter Maydell wrote:
>>> Possible current and future outbound interrupt lines (some of these
>>> would only show up in some unlikely or lots-of-implementation-needed
>>> cases, I'm just trying to produce an exhaustive list):
>>>  * virtual timer
>>>  * physical timer
>>>  * hyp timer (nested virtualization case)
>>>  * secure timer (unlikely but maybe if EL3 is ever supported inside a VM)
>>>  * gic maintenance interrupt (nested virt again)
>>>  * PMU interrupt
>>
>> Thanks for the list, that's good to have around for the future.
>>
>> There's also the potential of the EL2 virtual timer for nested VHE
>> support, right?
>
> That's the one I meant by "hyp timer".

VHE also adds an extra virtual timer, for symmetry with what EL1
provides (and on which CNTVOFF doesn't have any effect) - see section
B8.1.1 of the ARMv8.1 addendum. So we effectively have:

- Secure physical EL3
- Non-secure physical EL1
- Non-secure virtual EL1
- Non-secure physical EL2
- Non-secure virtual EL2

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny.