Hello Oleksandr, > On 2 Nov 2020, at 10:12 am, Oleksandr Andrushchenko > <[email protected]> wrote: > > Hi, > > On 11/2/20 11:55 AM, Bertrand Marquis wrote: >> Hi, >> >>> On 2 Nov 2020, at 05:55, Oleksandr Andrushchenko <[email protected]> wrote: >>> >>> Hi, Julien! >>> >>> On 10/30/20 7:18 PM, Julien Grall wrote: >>>> Hi Oleksandr, >>>> >>>> On 30/10/2020 10:44, Oleksandr Andrushchenko wrote: >>>>> On 10/20/20 6:25 PM, Rahul Singh wrote: >>>>>> Add support for ARM architected SMMUv3 implementations. It is based on >>>>>> the Linux SMMUv3 driver. >>>>>> >>>>>> Major differences between the Linux driver are as follows: >>>>>> 1. Only Stage-2 translation is supported as compared to the Linux driver >>>>>> that supports both Stage-1 and Stage-2 translations. >>>>> First of all thank you for the efforts! >>>>> >>>>> I tried the patch with QEMU and would like to know if my understanding >>>>> correct >>>>> >>>>> that this combination will not work as of now: >>>>> >>>>> (XEN) SMMUv3: /smmuv3@9050000: SMMUv3: DT value = eventq >>>>> (XEN) Data Abort Trap. Syndrome=0x1940010 >>>>> (XEN) Walking Hypervisor VA 0x40031000 on CPU0 via TTBR 0x00000000b8469000 >>>>> (XEN) 0TH[0x0] = 0x00000000b8468f7f >>>>> >>>>> [snip] >>>>> >>>>> If this is expected then is there any plan to make QEMU work as well? >>>>> >>>>> I see [1] says that "Only stage 1 and AArch64 PTW are supported." on QEMU >>>>> side. >>>> Just for clarication, you are trying to boot Xen on QEMU, right? >>> Exactly >>>> You might be able to use the stage-1 page-tables to isolate each device in >>>> Xen. However, I don't think you will be able to share the P2M because the >>>> page-tables layout between stage-1 and stage-2 is different. >>> So, it is even more work then >> Overall it would make more sense to spend some time adding proper support in >> Qemu then trying to modify the driver to support Qemu right now. >> >>>>> >>>>> We are interested in QEMU/SMMUv3 as a flexible platform for PCI >>>>> passthrough >>>>> >>>>> implementation, so it could allow testing different setups and >>>>> configurations with QEMU. >>>> I would recommend to get the SMMU supporting supporting stage-2 >>>> page-tables. >>> You mean in QEMU? >> See before. >> >>>> Regardless that, I think Xen should be able to say the SMMU is not >>>> supported rather than crashing. >>> Yes, that would be nice >> Fully agree and we will look into that. >> >> Anything you could share so that we could quickly reproduce your setup would >> be more then great. > > Nothing special, > > qemu/aarch64-softmmu/qemu-system-aarch64 -machine type=virt -machine > virt,gic-version=2 \ > > -machine virtualization=true -cpu cortex-a57 -smp 4 -m 2048 -nic > user,hostfwd=tcp:127.0.0.1:2222-:22 \ > > -nographic -serial mon:stdio [..snip..] > > I also set iommu to smmuv3 in my tests, QEMU emulator version 4.2.1
I just checked and confirmed that QEMU is booting with XEN SMMUv3 patch and XEN is able to say SMMU translation is not supported. As XEN supports Stage-2 translation and QEMU supports Stage-1 only. (XEN) SMMUv3: /smmuv3@9050000: SMMUv3: DT value = eventq (XEN) SMMUv3: /smmuv3@9050000: IDR0.COHACC overridden by FW configuration (false) (XEN) SMMUv3: /smmuv3@9050000: no translation support! (XEN) I/O virtualisation disabled Only difference I observed is that you have to add option "-machine virt,iommu=smmuv3 “ when launching the QEMU. Please let me know if it also works for you. > >> >> Regards >> Bertrand >> >>>> Cheers, >>>> >>> Thank you, >>> >>> Oleksandr
