diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
index 9eee284c80..e9cd3fb351 100644
--- a/hw/arm/virt-acpi-build.c
+++ b/hw/arm/virt-acpi-build.c
@@ -370,7 +370,7 @@ build_iort(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
         /* DeviceID mapping index (ignored since interrupts are GSIV based) */
         build_append_int_noprefix(table_data, 0, 4);
 
-        /* output IORT node is the ITS group node (the first node) */
+        /* Output IORT node is the ITS Group node (the first node) */
         build_iort_id_mapping(table_data, 0, 0x10000, IORT_NODE_OFFSET);
     }
 
@@ -407,23 +407,36 @@ build_iort(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
     if (vms->iommu == VIRT_IOMMU_SMMUV3) {
         AcpiIortIdMapping *range;
 
-        /* translated RIDs connect to SMMUv3 node: RC -> SMMUv3 -> ITS */
+        /*
+         * Map RIDs (input) from RC to SMMUv3 nodes: RC -> SMMUv3.
+         *
+         * N.B.: The mapping from SMMUv3 to ITS Group node (SMMUv3 -> ITS) is
+         * defined in the SMMUv3 table, where all SMMUv3 IDs are mapped to the
+         * ITS Group node.
+         */
         for (i = 0; i < smmu_idmaps->len; i++) {
             range = &g_array_index(smmu_idmaps, AcpiIortIdMapping, i);
-            /* output IORT node is the smmuv3 node */
+            /* Output IORT node is the SMMUv3 node. */
             build_iort_id_mapping(table_data, range->input_base,
                                   range->id_count, smmu_offset);
         }
 
-        /* bypassed RIDs connect to ITS group node directly: RC -> ITS */
+        /*
+         * Map bypassed (don't go throught the SMMU) RIDs (input) to ITS Group
+         * node directly: RC -> ITS.
+         */
         for (i = 0; i < its_idmaps->len; i++) {
             range = &g_array_index(its_idmaps, AcpiIortIdMapping, i);
-            /* output IORT node is the ITS group node (the first node) */
+            /* Output IORT node is the ITS Group node (the first node). */
             build_iort_id_mapping(table_data, range->input_base,
                                   range->id_count, IORT_NODE_OFFSET);
         }
     } else {
-        /* output IORT node is the ITS group node (the first node) */
+        /*
+         * Map all RIDs (input) to ITS Group node directly, since there is no
+         * SMMU: RC -> ITS.
+         * Output IORT node is the ITS Group node (the first node).
+         */
         build_iort_id_mapping(table_data, 0, 0x10000, IORT_NODE_OFFSET);
     }