hw/i386/q35: Set virtio-iommu aw-bits default value to 39

Currently the default input range can extend to 64 bits. On x86,
when the virtio-iommu protects vfio devices, the physical iommu
may support only 39 bits. Let's set the default to 39, as done
for the intel-iommu.

We use hw_compat_8_2 to handle the compatibility for machines
before 9.0 which used to have a virtio-iommu default input range
of 64 bits.

Of course if aw-bits is set from the command line, the default
is overriden.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Message-Id: <20240307134445.92296-8-eric.auger@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/hw/core/machine.c b/hw/core/machine.c
index 6bd09d4592..4b89172d1c 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -35,6 +35,7 @@
 
 GlobalProperty hw_compat_8_2[] = {
     { TYPE_VIRTIO_IOMMU_PCI, "granule", "4k" },
+    { TYPE_VIRTIO_IOMMU_PCI, "aw-bits", "64" },
 };
 const size_t hw_compat_8_2_len = G_N_ELEMENTS(hw_compat_8_2);