> -----Original Message----- > From: Eric Auger <eric.au...@redhat.com> > Sent: Wednesday, March 12, 2025 4:28 PM > To: Shameerali Kolothum Thodi > <shameerali.kolothum.th...@huawei.com>; qemu-...@nongnu.org; > qemu-devel@nongnu.org > Cc: peter.mayd...@linaro.org; j...@nvidia.com; nicol...@nvidia.com; > ddut...@redhat.com; berra...@redhat.com; nath...@nvidia.com; > mo...@nvidia.com; smost...@google.com; Linuxarm > <linux...@huawei.com>; Wangzhou (B) <wangzh...@hisilicon.com>; > jiangkunkun <jiangkun...@huawei.com>; Jonathan Cameron > <jonathan.came...@huawei.com>; zhangfei....@linaro.org > Subject: Re: [RFC PATCH v2 04/20] hw/arm/virt: Add support for smmuv3- > accel
> >> Hi Shameer, > >>>> I know there were quite a lot of dicussions on the 1st multi > >>>> instantiation series related to the way we instanatiate that device > >>>> and maybe I missed some blockers but why wouldn't we allow the > >>>> instantiation of the legacy smmu device with -device too. I think > >>>> this would be simpler for libvirt and we would somehow deprecate > >>>> the machine option method? would that make a problem if you were > to > >>>> use -device smmu,accel or something alike? > >>> Thanks for taking a look. I am just jumping on this one for now. > >>> Yes, there were discussions around that. But I was not sure we > >>> concluded on deprecating the machine option. So if I get you > >>> correctly the idea is, > >>> > >>> if we have, > >>> -device smmuv3 it will instantiate the current machine wide smmuv3 > >>> and for -device smmuv3,accel this device? > >> yes that would be my preference. > > Ok. I will look into that in my next respin. A quick question. Does > > qemu DEVICE model support the differentiation like above easily? Or we > > have to manage it with properties? > Not sure if I understand you question. I meant it can be a boolean device > property (DEFINE_PROP_BOOL) smmuv3,accel=on > > No? Right. My query was more about any hidden Qemu magic to have device instantiation similar to what we have at the moment even though we name both devices "smmuv3". That way I can keep much of the code rather than checking "accel" property in SMMUv3 code and redirecting calls. But looks like not. Thanks, Shameer
