From: Nathan Chen <nathanc@nvidia.com>

Set the default ssidsize value to auto. The default SSID size used
to be 0, but we change it to match what the host IOMMU properties
report so that users do not have to introspect host IDR1 for the
Substream ID support.

Signed-off-by: Nathan Chen <nathanc@nvidia.com>
---
 hw/arm/smmuv3.c   | 4 ++--
 hw/core/machine.c | 1 +
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/hw/arm/smmuv3.c b/hw/arm/smmuv3.c
index 67c499d22b..cb14a08a66 100644
--- a/hw/arm/smmuv3.c
+++ b/hw/arm/smmuv3.c
@@ -2156,7 +2156,7 @@ static const Property smmuv3_properties[] = {
     DEFINE_PROP_ON_OFF_AUTO("ats", SMMUv3State, ats, ON_OFF_AUTO_AUTO),
     DEFINE_PROP_OAS_MODE("oas", SMMUv3State, oas, OAS_MODE_44),
     DEFINE_PROP_SSIDSIZE_MODE("ssidsize", SMMUv3State, ssidsize,
-                              SSID_SIZE_MODE_0),
+                              SSID_SIZE_MODE_AUTO),
 };
 
 static void smmuv3_instance_init(Object *obj)
@@ -2195,7 +2195,7 @@ static void smmuv3_class_init(ObjectClass *klass, const void *data)
         "Number of bits used to represent SubstreamIDs (SSIDs). "
         "A value of N allows SSIDs in the range [0 .. 2^N - 1]. "
         "Valid range is 0-20, where 0 disables SubstreamID support. "
-        "Defaults to 0. A value greater than 0 is required to enable "
+        "Defaults to auto. A value greater than 0 is required to enable "
         "PASID support.");
 }
 
diff --git a/hw/core/machine.c b/hw/core/machine.c
index 8f8c26bbe8..aa208a2d9a 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -42,6 +42,7 @@
 GlobalProperty hw_compat_11_0[] = {
     { TYPE_ARM_SMMUV3, "ats", "off" },
     { TYPE_ARM_SMMUV3, "ril", "on" },
+    { TYPE_ARM_SMMUV3, "ssidsize", "0" },
 };
 
 GlobalProperty hw_compat_10_2[] = {
-- 
2.43.0