Re: SMMU Stage 2 translation in QEMU

[Peter Maydell]

On Thu, 9 Sept 2021 at 21:18, <shashi.mallela@linaro.org> wrote:
> I am trying to understand the approach required for an emulated SMMU to
> convert IPAs(from each qemu guest) to PAs(respective host addresses)
> using stage 2 tables.
>
> The questions i have are:-
>
> 1) Since SMMU stage 2 tables are expected to be created and managed by
> a hypervisor,if there is no kvm support,who is responsible to create
> the stage 2 tables in host memory? is it even a valid use case to
> consider smmu stage 2 support with no hypervisor present?

So what exactly is the use case you're talking about here?
Do you mean "purely emulated QEMU, but using a host hardware
IOMMU to do device passthrough of host devices to the guest"?
Or do you mean "purely emulated QEMU with an emulated SMMU
that handles accesses to emulated devices" ?

thanks
-- PMM