Re: [RFC PATCH 0/5] hw/arm/virt: Add support for user-creatable nested SMMUv3

[Mostafa Saleh <smostafa@google.com>]

Hi Shameer,

On Thu, Nov 14, 2024 at 08:01:28AM +0000, Shameerali Kolothum Thodi wrote:
> Hi Mostafa,
> 
> > -----Original Message-----
> > From: Mostafa Saleh <smostafa@google.com>
> > Sent: Wednesday, November 13, 2024 4:17 PM
> > To: Shameerali Kolothum Thodi <shameerali.kolothum.thodi@huawei.com>
> > Cc: qemu-arm@nongnu.org; qemu-devel@nongnu.org;
> > eric.auger@redhat.com; peter.maydell@linaro.org; jgg@nvidia.com;
> > nicolinc@nvidia.com; ddutile@redhat.com; Linuxarm
> > <linuxarm@huawei.com>; Wangzhou (B) <wangzhou1@hisilicon.com>;
> > jiangkunkun <jiangkunkun@huawei.com>; Jonathan Cameron
> > <jonathan.cameron@huawei.com>; zhangfei.gao@linaro.org
> > Subject: Re: [RFC PATCH 0/5] hw/arm/virt: Add support for user-creatable
> > nested SMMUv3
> > 
> > Hi Shameer,
> > 
> > On Fri, Nov 08, 2024 at 12:52:37PM +0000, Shameer Kolothum via wrote:
> > > Hi,
> > >
> > > This series adds initial support for a user-creatable "arm-smmuv3-nested"
> > > device to Qemu. At present the Qemu ARM SMMUv3 emulation is per
> > machine
> > > and cannot support multiple SMMUv3s.
> > >
> > 
> > I had a quick look at the SMMUv3 files, as now SMMUv3 supports nested
> > translation emulation, would it make sense to rename this? As AFAIU,
> > this is about virt (stage-1) SMMUv3 that is emulated to a guest.
> > Including vSMMU or virt would help distinguish the code, as now
> > some new function as smmu_nested_realize() looks confusing.
> 
> Yes. I have noticed that. We need to call it something else to avoid the 
> confusion. Not sure including "virt" is a good idea as it may indicate virt
> machine. Probably "acc" as Nicolin suggested to indicate hw accelerated. 
> I will think about a better one. Open to suggestions.

"acc" sounds good to me, also if possible we can have smmuv3-acc.c where
it has all the specific logic, and the main file just calls into it.

Thanks,
Mostafa

> 
> Thanks,
> Shameer
>