Add an "identifier" property to the SMMUv3 device and use it when
building the ACPI IORT SMMUv3 node Identifier field.

This avoids relying on device enumeration order and provides a stable
per-device identifier. A subsequent patch will use the same identifier
when generating the DSDT description for Tegra241 CMDQV, ensuring that
the IORT and DSDT entries refer to the same SMMUv3 instance.

No functional change intended.

Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Shameer Kolothum <skolothumtho@nvidia.com>
---
 include/hw/arm/smmuv3.h  | 1 +
 hw/arm/smmuv3.c          | 2 ++
 hw/arm/virt-acpi-build.c | 4 +++-
 hw/arm/virt.c            | 3 +++
 4 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/include/hw/arm/smmuv3.h b/include/hw/arm/smmuv3.h
index 648412cafc..73b8f39aaa 100644
--- a/include/hw/arm/smmuv3.h
+++ b/include/hw/arm/smmuv3.h
@@ -63,6 +63,7 @@ struct SMMUv3State {
     qemu_irq     irq[4];
     QemuMutex mutex;
     char *stage;
+    uint8_t identifier;
 
     /* SMMU has HW accelerator support for nested S1 + s2 */
     bool accel;
diff --git a/hw/arm/smmuv3.c b/hw/arm/smmuv3.c
index 468135bb24..c1f84bedd4 100644
--- a/hw/arm/smmuv3.c
+++ b/hw/arm/smmuv3.c
@@ -2109,6 +2109,8 @@ static const Property smmuv3_properties[] = {
      * Defaults to stage 1
      */
     DEFINE_PROP_STRING("stage", SMMUv3State, stage),
+    /* Identifier used for ACPI IORT SMMUv3 (and DSDT for CMDQV) generation */
+    DEFINE_PROP_UINT8("identifier", SMMUv3State, identifier, 0),
     DEFINE_PROP_BOOL("accel", SMMUv3State, accel, false),
     /* GPA of MSI doorbell, for SMMUv3 accel use. */
     DEFINE_PROP_UINT64("msi-gpa", SMMUv3State, msi_gpa, 0),
diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
index ae78e9b9e0..20605185c5 100644
--- a/hw/arm/virt-acpi-build.c
+++ b/hw/arm/virt-acpi-build.c
@@ -342,6 +342,7 @@ static int iort_idmap_compare(gconstpointer a, gconstpointer b)
 typedef struct AcpiIortSMMUv3Dev {
     int irq;
     hwaddr base;
+    uint8_t id;
     GArray *rc_smmu_idmaps;
     /* Offset of the SMMUv3 IORT Node relative to the start of the IORT */
     size_t offset;
@@ -404,6 +405,7 @@ static int populate_smmuv3_dev(GArray *sdev_blob, VirtMachineState *vms)
                                                &error_abort));
         sdev.accel = object_property_get_bool(obj, "accel", &error_abort);
         sdev.ats = object_property_get_bool(obj, "ats", &error_abort);
+        sdev.id = object_property_get_uint(obj, "identifier", &error_abort);
         pbus = PLATFORM_BUS_DEVICE(vms->platform_bus_dev);
         sbdev = SYS_BUS_DEVICE(obj);
         sdev.base = platform_bus_get_mmio_addr(pbus, sbdev, 0);
@@ -630,7 +632,7 @@ build_iort(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
                      (ID_MAPPING_ENTRY_SIZE * smmu_mapping_count);
         build_append_int_noprefix(table_data, node_size, 2); /* Length */
         build_append_int_noprefix(table_data, 4, 1); /* Revision */
-        build_append_int_noprefix(table_data, id++, 4); /* Identifier */
+        build_append_int_noprefix(table_data, sdev->id, 4); /* Identifier */
         /* Number of ID mappings */
         build_append_int_noprefix(table_data, smmu_mapping_count, 4);
         /* Reference to ID Array */
diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index c75a8d6e9e..44c6b99c96 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -3138,6 +3138,7 @@ static void virt_memory_plug(HotplugHandler *hotplug_dev,
     }
 }
 
+static uint8_t smmuv3_dev_id;
 static void virt_machine_device_pre_plug_cb(HotplugHandler *hotplug_dev,
                                             DeviceState *dev, Error **errp)
 {
@@ -3196,6 +3197,8 @@ static void virt_machine_device_pre_plug_cb(HotplugHandler *hotplug_dev,
                                      OBJECT(vms->sysmem), NULL);
             object_property_set_link(OBJECT(dev), "secure-memory",
                                      OBJECT(vms->secure_sysmem), NULL);
+            object_property_set_uint(OBJECT(dev), "identifier", smmuv3_dev_id++,
+                                     NULL);
         }
         if (object_property_get_bool(OBJECT(dev), "accel", &error_abort)) {
             hwaddr db_start = 0;
-- 
2.43.0