Commit 9f8a8e0f2c for qemu.org

commit 9f8a8e0f2c6fd48b4f3759a02b5210cba6a978e3
Author: Nathan Chen <nathanc@nvidia.com>
Date:   Tue Mar 24 14:02:29 2026 +0000

    hw/arm/smmuv3-accel: Change "ats" property type to OnOffAuto

    Change accel SMMUv3 ATS property from bool to OnOffAuto. The 'auto'
    value is not implemented, as this commit is meant to set the property
    to the correct type and avoid breaking JSON/QMP when the auto mode is
    introduced. A future patch will implement resolution of the 'auto'
    value to match the host SMMUv3 ATS support.

    The conversion of the ATS property type to OnOffAuto is an
    incompatible change for JSON/QMP when a bool value is expected for
    "ats", but the "ats" property is new in 11.0 and this patch is
    submitted as a fix to the property type.

    Fixes: f7f5013a55a3 ("hw/arm/smmuv3-accel: Add support for ATS")
    Tested-by: Eric Auger <eric.auger@redhat.com>
    Reviewed-by: Shameer Kolothum <skolothumtho@nvidia.com>
    Tested-by: Shameer Kolothum <skolothumtho@nvidia.com>
    Reviewed-by: Eric Auger <eric.auger@redhat.com>
    Acked-by: Markus Armbruster <armbru@redhat.com>
    Signed-off-by: Nathan Chen <nathanc@nvidia.com>
    Message-id: 20260323182454.1416110-3-nathanc@nvidia.com
    Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/hw/arm/smmuv3-accel.c b/hw/arm/smmuv3-accel.c
index 2bb142c47f..f21a6a9997 100644
--- a/hw/arm/smmuv3-accel.c
+++ b/hw/arm/smmuv3-accel.c
@@ -827,7 +827,9 @@ void smmuv3_accel_idr_override(SMMUv3State *s)
     s->idr[3] = FIELD_DP32(s->idr[3], IDR3, RIL, s->ril);

     /* QEMU SMMUv3 has no ATS. Advertise ATS if opt-in by property */
-    s->idr[0] = FIELD_DP32(s->idr[0], IDR0, ATS, s->ats);
+    if (s->ats == ON_OFF_AUTO_ON) {
+        s->idr[0] = FIELD_DP32(s->idr[0], IDR0, ATS, 1);
+    }

     /* Advertise 48-bit OAS in IDR5 when requested (default is 44 bits). */
     if (s->oas == SMMU_OAS_48BIT) {
diff --git a/hw/arm/smmuv3.c b/hw/arm/smmuv3.c
index 068108e49b..a683402a0c 100644
--- a/hw/arm/smmuv3.c
+++ b/hw/arm/smmuv3.c
@@ -317,6 +317,11 @@ static void smmuv3_init_id_regs(SMMUv3State *s)
     smmuv3_accel_idr_override(s);
 }

+bool smmuv3_ats_enabled(SMMUv3State *s)
+{
+    return FIELD_EX32(s->idr[0], IDR0, ATS);
+}
+
 static void smmuv3_reset(SMMUv3State *s)
 {
     s->cmdq.base = deposit64(s->cmdq.base, 0, 5, SMMU_CMDQS);
@@ -1966,12 +1971,17 @@ static bool smmu_validate_property(SMMUv3State *s, Error **errp)
     }
 #endif

+    if (s->ats == ON_OFF_AUTO_AUTO) {
+        error_setg(errp, "ats auto mode is not supported");
+        return false;
+    }
+
     if (!s->accel) {
         if (!s->ril) {
             error_setg(errp, "ril can only be disabled if accel=on");
             return false;
         }
-        if (s->ats) {
+        if (s->ats == ON_OFF_AUTO_ON) {
             error_setg(errp, "ats can only be enabled if accel=on");
             return false;
         }
@@ -2128,7 +2138,7 @@ static const Property smmuv3_properties[] = {
     DEFINE_PROP_UINT64("msi-gpa", SMMUv3State, msi_gpa, 0),
     /* RIL can be turned off for accel cases */
     DEFINE_PROP_BOOL("ril", SMMUv3State, ril, true),
-    DEFINE_PROP_BOOL("ats", SMMUv3State, ats, false),
+    DEFINE_PROP_ON_OFF_AUTO("ats", SMMUv3State, ats, ON_OFF_AUTO_OFF),
     DEFINE_PROP_UINT8("oas", SMMUv3State, oas, 44),
     DEFINE_PROP_UINT8("ssidsize", SMMUv3State, ssidsize, 0),
 };
@@ -2160,7 +2170,8 @@ static void smmuv3_class_init(ObjectClass *klass, const void *data)
         "Disable range invalidation support (for accel=on)");
     object_class_property_set_description(klass, "ats",
         "Enable/disable ATS support (for accel=on). Please ensure host "
-        "platform has ATS support before enabling this");
+        "platform has ATS support before enabling this. ats=auto is not "
+        "supported.");
     object_class_property_set_description(klass, "oas",
         "Specify Output Address Size (for accel=on). Supported values "
         "are 44 or 48 bits. Defaults to 44 bits");
diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
index 719d2f994e..591cfc993c 100644
--- a/hw/arm/virt-acpi-build.c
+++ b/hw/arm/virt-acpi-build.c
@@ -402,7 +402,7 @@ static int iort_smmuv3_devices(Object *obj, void *opaque)

     bus = PCI_BUS(object_property_get_link(obj, "primary-bus", &error_abort));
     sdev.accel = object_property_get_bool(obj, "accel", &error_abort);
-    sdev.ats = object_property_get_bool(obj, "ats", &error_abort);
+    sdev.ats = smmuv3_ats_enabled(ARM_SMMUV3(obj));
     pbus = PLATFORM_BUS_DEVICE(vms->platform_bus_dev);
     sbdev = SYS_BUS_DEVICE(obj);
     sdev.base = platform_bus_get_mmio_addr(pbus, sbdev, 0);
diff --git a/include/hw/arm/smmuv3.h b/include/hw/arm/smmuv3.h
index 26b2fc42fd..ce51a5b9b4 100644
--- a/include/hw/arm/smmuv3.h
+++ b/include/hw/arm/smmuv3.h
@@ -70,7 +70,7 @@ struct SMMUv3State {
     uint64_t msi_gpa;
     Error *migration_blocker;
     bool ril;
-    bool ats;
+    OnOffAuto ats;
     uint8_t oas;
     uint8_t ssidsize;
 };
@@ -91,6 +91,8 @@ struct SMMUv3Class {
     ResettablePhases parent_phases;
 };

+bool smmuv3_ats_enabled(struct SMMUv3State *s);
+
 #define TYPE_ARM_SMMUV3   "arm-smmuv3"
 OBJECT_DECLARE_TYPE(SMMUv3State, SMMUv3Class, ARM_SMMUV3)