Hi Shameer,
On 9/29/25 3:36 PM, Shameer Kolothum wrote:
> Here we return the IOMMU address space if the device has S1 translation
> enabled by Guest. Otherwise return system address space.
>
> Signed-off-by: Shameer Kolothum <[email protected]>
> Signed-off-by: Shameer Kolothum <[email protected]>
> ---
> hw/arm/smmuv3-accel.c | 21 +++++++++++++++++++++
> 1 file changed, 21 insertions(+)
>
> diff --git a/hw/arm/smmuv3-accel.c b/hw/arm/smmuv3-accel.c
> index 790887ac31..f4e01fba6d 100644
> --- a/hw/arm/smmuv3-accel.c
> +++ b/hw/arm/smmuv3-accel.c
> @@ -387,6 +387,26 @@ static void smmuv3_accel_unset_iommu_device(PCIBus *bus,
> void *opaque,
> }
> }
>
> +static AddressSpace *smmuv3_accel_find_msi_as(PCIBus *bus, void *opaque,
> + int devfn)
> +{
> + SMMUState *bs = opaque;
> + SMMUPciBus *sbus = smmu_get_sbus(bs, bus);
> + SMMUv3AccelDevice *accel_dev = smmuv3_accel_get_dev(bs, sbus, bus,
> devfn);
> + SMMUDevice *sdev = &accel_dev->sdev;
> +
> + /*
> + * If the assigned vfio-pci dev has S1 translation enabled by
> + * Guest, return IOMMU address space for MSI translation.
> + * Otherwise, return system address space.
> + */
> + if (accel_dev->s1_hwpt) {
> + return &sdev->as;
> + } else {
> + return &address_space_memory;
> + }
At the moment I don't understand this code either. In case of emulated
device it then returns address_space_memory whereas I would have
expected the opposite. I definitively need to trace things ;-)
Thanks
Eric
> +}
> +
> static bool smmuv3_accel_pdev_allowed(PCIDevice *pdev, bool *vfio_pci)
> {
>
> @@ -475,6 +495,7 @@ static const PCIIOMMUOps smmuv3_accel_ops = {
> .get_viommu_flags = smmuv3_accel_get_viommu_flags,
> .set_iommu_device = smmuv3_accel_set_iommu_device,
> .unset_iommu_device = smmuv3_accel_unset_iommu_device,
> + .get_msi_address_space = smmuv3_accel_find_msi_as,
> };
>
> void smmuv3_accel_init(SMMUv3State *s)
