1 files changed, 98 insertions, 0 deletions
diff --git a/DynamicTablesPkg/Library/Common/AmlLib/Tree/AmlTreeEnumerator.c b/DynamicTablesPkg/Library/Common/AmlLib/Tree/AmlTreeEnumerator.c
new file mode 100644
index 0000000000..3eeb7253bf
--- /dev/null
+++ b/DynamicTablesPkg/Library/Common/AmlLib/Tree/AmlTreeEnumerator.c
@@ -0,0 +1,98 @@
+/** @file
+  AML Tree Enumerator.
+
+  Copyright (c) 2019 - 2020, Arm Limited. All rights reserved.<BR>
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#include <AmlNodeDefines.h>
+
+#include <AmlCoreInterface.h>
+#include <Tree/AmlTree.h>
+
+/** Enumerate all nodes of the subtree under the input Node in the AML
+    bytestream order (i.e. in a depth first order), and call the CallBack
+    function with the input Context.
+    The prototype of the Callback function is EDKII_AML_TREE_ENUM_CALLBACK.
+
+  @param  [in]      Node      Enumerate nodes of the subtree under this Node.
+                              Must be a valid node.
+  @param  [in]      CallBack  Callback function to call on each node.
+  @param  [in, out] Context   Void pointer used to pass some information
+                              to the Callback function.
+                              Optional, can be NULL.
+  @param  [out]     Status    Optional parameter that can be used to get
+                              the status of the Callback function.
+                              If used, need to be init to EFI_SUCCESS.
+
+  @retval TRUE if the enumeration can continue or has finished without
+          interruption.
+  @retval FALSE if the enumeration needs to stopped or has stopped.
+**/
+BOOLEAN
+EFIAPI
+AmlEnumTree (
+  IN      AML_NODE_HEADER               * Node,
+  IN      EDKII_AML_TREE_ENUM_CALLBACK    CallBack,
+  IN  OUT VOID                          * Context,  OPTIONAL
+      OUT EFI_STATUS                    * Status    OPTIONAL
+  )
+{
+  BOOLEAN               ContinueEnum;
+
+  EAML_PARSE_INDEX      Index;
+  EAML_PARSE_INDEX      MaxIndex;
+
+  LIST_ENTRY          * StartLink;
+  LIST_ENTRY          * CurrentLink;
+
+  if (!IS_AML_NODE_VALID (Node) || (CallBack == NULL)) {
+    ASSERT (0);
+    if (Status != NULL) {
+      *Status = EFI_INVALID_PARAMETER;
+    }
+    return FALSE;
+  }
+
+  ContinueEnum = (*CallBack)(Node, Context, Status);
+  if (ContinueEnum == FALSE) {
+    return ContinueEnum;
+  }
+
+  // Iterate through the fixed list of arguments.
+  MaxIndex = (EAML_PARSE_INDEX)AmlGetFixedArgumentCount (
+                                 (AML_OBJECT_NODE*)Node
+                                 );
+  for (Index = EAmlParseIndexTerm0; Index < MaxIndex; Index++) {
+    ContinueEnum = AmlEnumTree (
+                     AmlGetFixedArgument ((AML_OBJECT_NODE*)Node, Index),
+                     CallBack,
+                     Context,
+                     Status
+                     );
+    if (ContinueEnum == FALSE) {
+      return ContinueEnum;
+    }
+  }
+
+  // Iterate through the variable list of arguments.
+  StartLink = AmlNodeGetVariableArgList (Node);
+  if (StartLink != NULL) {
+    CurrentLink = StartLink->ForwardLink;
+    while (CurrentLink != StartLink) {
+      ContinueEnum = AmlEnumTree (
+                       (AML_NODE_HEADER*)CurrentLink,
+                       CallBack,
+                       Context,
+                       Status
+                       );
+      if (ContinueEnum == FALSE) {
+        return ContinueEnum;
+      }
+      CurrentLink = CurrentLink->ForwardLink;
+    } // while
+  }
+
+  return ContinueEnum;
+}