[PATCH v4 1/4] virtio-iommu: Add an option to define the input range width

[Eric Auger <eric.auger@redhat.com>]

aw-bits is a new option that allows to set the bit width of
the input address range. This value will be used as a default for
the device config input_range.end. By default it is set to 64 bits
which is the current value.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>

---

v1 -> v2:
- Check the aw-bits value is within [32,64]
---
 include/hw/virtio/virtio-iommu.h | 1 +
 hw/virtio/virtio-iommu.c         | 7 ++++++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/include/hw/virtio/virtio-iommu.h b/include/hw/virtio/virtio-iommu.h
index 781ebaea8f..5fbe4677c2 100644
--- a/include/hw/virtio/virtio-iommu.h
+++ b/include/hw/virtio/virtio-iommu.h
@@ -66,6 +66,7 @@ struct VirtIOIOMMU {
     bool boot_bypass;
     Notifier machine_done;
     bool granule_frozen;
+    uint8_t aw_bits;
 };
 
 #endif
diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
index 8a4bd933c6..666c41fe64 100644
--- a/hw/virtio/virtio-iommu.c
+++ b/hw/virtio/virtio-iommu.c
@@ -1314,7 +1314,11 @@ static void virtio_iommu_device_realize(DeviceState *dev, Error **errp)
      */
     s->config.bypass = s->boot_bypass;
     s->config.page_size_mask = qemu_target_page_mask();
-    s->config.input_range.end = UINT64_MAX;
+    if (s->aw_bits < 32 || s->aw_bits > 64) {
+        error_setg(errp, "aw-bits must be within [32,64]");
+    }
+    s->config.input_range.end =
+        s->aw_bits == 64 ? UINT64_MAX : BIT_ULL(s->aw_bits) - 1;
     s->config.domain_range.end = UINT32_MAX;
     s->config.probe_size = VIOMMU_PROBE_SIZE;
 
@@ -1522,6 +1526,7 @@ static Property virtio_iommu_properties[] = {
     DEFINE_PROP_LINK("primary-bus", VirtIOIOMMU, primary_bus,
                      TYPE_PCI_BUS, PCIBus *),
     DEFINE_PROP_BOOL("boot-bypass", VirtIOIOMMU, boot_bypass, true),
+    DEFINE_PROP_UINT8("aw-bits", VirtIOIOMMU, aw_bits, 64),
     DEFINE_PROP_END_OF_LIST(),
 };
 
-- 
2.41.0