board_inspector: add object_type codes in Decls

Object type codes are used to identify, as the name suggests, type of
objects. Typical object types in AML include integers, strings, methods,
devices, buffers, packages and operation regions. In DefExternal terms the
object type codes help specify the type of the external objects so that an
AML parser can parse the code without knowing the concrete definition of
these objects.

The per-device AML templates in board XMLs need DefExternal terms to
declare the objects in other devices, as these templates are meant to be
parsed and integrated separately. This patch adds a static method to object
declaration classes to make it easier to generate such DefExternal terms
for a given declaration.

A complete definition of object type codes can be found in section 19.6.96
of ACPI specification 6.4.

v1 -> v2:
  * Remove the object_type of FieldDecl and OperationFieldDecl as 0x5 is
    not a proper object type for buffer fields.

Tracked-On: #6287
Signed-off-by: Junjie Mao <junjie.mao@intel.com>

misc/config_tools/board_inspector/acpiparser/aml/context.py

@@ -11,6 +11,10 @@ from .exception import *
 from .stream import Stream
 
 class NamedDecl:
+    @staticmethod
+    def object_type():
+        return 0
+
     def __init__(self, name, tree):
         self.tree = tree
         self.name = name
@@ -66,6 +70,10 @@ class AliasDecl(NamedDecl):
         print(f"{self.name}: {self.__class__.__name__}, aliasing {self.source}")
 
 class MethodDecl(NamedDecl):
+    @staticmethod
+    def object_type():
+        return 8
+
     def __init__(self, name, nargs, tree):
         super().__init__(name, tree)
         self.nargs = nargs
@@ -74,6 +82,10 @@ class MethodDecl(NamedDecl):
         print(f"{self.name}: {self.__class__.__name__}, {self.nargs} args")
 
 class PredefinedMethodDecl(NamedDecl):
+    @staticmethod
+    def object_type():
+        return 8
+
     def __init__(self, name, nargs, fn):
         super().__init__(name, None)
         self.nargs = nargs
@@ -83,6 +95,10 @@ class PredefinedMethodDecl(NamedDecl):
         print(f"{self.name}: {self.__class__.__name__}, {self.nargs} args")
 
 class DeviceDecl(NamedDecl):
+    @staticmethod
+    def object_type():
+        return 6
+
     def __init__(self, name, tree):
         super().__init__(name, tree)
 

misc/config_tools/board_inspector/acpiparser/aml/parser.py

@@ -501,7 +501,7 @@ def DefExternal_hook_post(context, tree):
     ty = tree.ObjectType.value
     nargs = tree.ArgumentCount.value
 
-    if ty == 0x8:     # an external method
+    if ty == MethodDecl.object_type():
         sym = MethodDecl(name, nargs, tree)
     else:
         sym = NamedDecl(name, tree)