DynamicTablesPkg/Include/Library/AmlLib/AmlLib.h

   1 /** @file
   2   AML Lib.
   3
   4   Copyright (c) 2019 - 2020, Arm Limited. All rights reserved.<BR>
   5
   6   SPDX-License-Identifier: BSD-2-Clause-Patent
   7 **/
   8
   9 #ifndef AML_LIB_H_
  10 #define AML_LIB_H_
  11
  12 /**
  13   @mainpage Dynamic AML Generation
  14   @{
  15     @par Summary
  16     @{
  17     ACPI tables are categorized as data tables and definition block
  18     tables. Dynamic Tables Framework currently supports generation of ACPI
  19     data tables. Generation of definition block tables is difficult as these
  20     tables are encoded in ACPI Machine Language (AML), which has a complex
  21     grammar.
  22
  23     Dynamic AML Generation is an extension to the Dynamic tables Framework.
  24     One of the techniques used to simplify definition block generation is to
  25     fixup a template SSDT table.
  26
  27     Dynamic AML aims to provide a framework that allows fixing up of an ACPI
  28     SSDT template with appropriate information about the hardware.
  29
  30     This framework consists of an:
  31     - AMLLib core that implements a rich set of interfaces to parse, traverse
  32       and update AML data.
  33     - AMLLib library APIs that provides interfaces to search and updates nodes
  34       in the AML namespace.
  35     @}
  36   @}
  37 */
  38
  39 #include <IndustryStandard/Acpi.h>
  40
  41 #ifndef AML_HANDLE
  42
  43 /** Node handle.
  44 */
  45 typedef void* AML_NODE_HANDLE;
  46
  47 /** Root Node handle.
  48 */
  49 typedef void* AML_ROOT_NODE_HANDLE;
  50
  51 /** Object Node handle.
  52 */
  53 typedef void* AML_OBJECT_NODE_HANDLE;
  54
  55 /** Data Node handle.
  56 */
  57 typedef void* AML_DATA_NODE_HANDLE;
  58
  59 #endif // AML_HANDLE
  60
  61 /** Parse the definition block.
  62
  63   The function parses the whole AML blob. It starts with the ACPI DSDT/SSDT
  64   header and then parses the AML bytestream.
  65   A tree structure is returned via the RootPtr.
  66   The tree must be deleted with the AmlDeleteTree function.
  67
  68   @ingroup UserApis
  69
  70   @param  [in]  DefinitionBlock   Pointer to the definition block.
  71   @param  [out] RootPtr           Pointer to the root node of the AML tree.
  72
  73   @retval EFI_SUCCESS             The function completed successfully.
  74   @retval EFI_BUFFER_TOO_SMALL    No space left in the buffer.
  75   @retval EFI_INVALID_PARAMETER   Invalid parameter.
  76   @retval EFI_OUT_OF_RESOURCES    Could not allocate memory.
  77 **/
  78 EFI_STATUS
  79 EFIAPI
  80 AmlParseDefinitionBlock (
  81   IN  CONST EFI_ACPI_DESCRIPTION_HEADER   * DefinitionBlock,
  82   OUT       AML_ROOT_NODE_HANDLE          * RootPtr
  83   );
  84
  85 /** Serialize an AML definition block.
  86
  87   This functions allocates memory with the "AllocateZeroPool ()"
  88   function. This memory is used to serialize the AML tree and is
  89   returned in the Table.
  90
  91   @ingroup UserApis
  92
  93   @param [in]  RootNode         Root node of the tree.
  94   @param [out] Table            On return, hold the serialized
  95                                 definition block.
  96
  97   @retval EFI_SUCCESS            The function completed successfully.
  98   @retval EFI_INVALID_PARAMETER  Invalid parameter.
  99   @retval EFI_OUT_OF_RESOURCES   Could not allocate memory.
 100 **/
 101 EFI_STATUS
 102 EFIAPI
 103 AmlSerializeDefinitionBlock (
 104   IN  AML_ROOT_NODE_HANDLE              RootNode,
 105   OUT EFI_ACPI_DESCRIPTION_HEADER    ** Table
 106   );
 107
 108 /** Clone a node and its children (clone a tree branch).
 109
 110   The cloned branch returned is not attached to any tree.
 111
 112   @ingroup UserApis
 113
 114   @param  [in]  Node        Pointer to a node.
 115                             Node is the head of the branch to clone.
 116   @param  [out] ClonedNode  Pointer holding the head of the created cloned
 117                             branch.
 118
 119   @retval EFI_SUCCESS             The function completed successfully.
 120   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 121   @retval EFI_OUT_OF_RESOURCES    Could not allocate memory.
 122 **/
 123 EFI_STATUS
 124 EFIAPI
 125 AmlCloneTree (
 126   IN  AML_NODE_HANDLE   Node,
 127   OUT AML_NODE_HANDLE * ClonedNode
 128   );
 129
 130 /** Delete a Node and its children.
 131
 132   The Node must be removed from the tree first,
 133   or must be the root node.
 134
 135   @ingroup UserApis
 136
 137   @param  [in]  Node  Pointer to the node to delete.
 138
 139   @retval EFI_SUCCESS             The function completed successfully.
 140   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 141 **/
 142 EFI_STATUS
 143 EFIAPI
 144 AmlDeleteTree (
 145   IN  AML_NODE_HANDLE   Node
 146   );
 147
 148 /** Detach the Node from the tree.
 149
 150   The function will fail if the Node is in its parent's fixed
 151   argument list.
 152   The Node is not deleted. The deletion is done separately
 153   from the removal.
 154
 155   @ingroup UserApis
 156
 157   @param  [in]  Node  Pointer to a Node.
 158                       Must be a data node or an object node.
 159
 160   @retval EFI_SUCCESS             The function completed successfully.
 161   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 162 **/
 163 EFI_STATUS
 164 EFIAPI
 165 AmlDetachNode (
 166   IN  AML_NODE_HANDLE   Node
 167   );
 168
 169 /** Find a node in the AML namespace, given an ASL path and a reference Node.
 170
 171    - The AslPath can be an absolute path, or a relative path from the
 172      reference Node;
 173    - Node must be a root node or a namespace node;
 174    - A root node is expected to be at the top of the tree.
 175
 176   E.g.:
 177   For the following AML namespace, with the ReferenceNode being the node with
 178   the name "AAAA":
 179    - the node with the name "BBBB" can be found by looking for the ASL
 180      path "BBBB";
 181    - the root node can be found by looking for the ASL relative path "^",
 182       or the absolute path "\\".
 183
 184   AML namespace:
 185   \
 186   \-AAAA      <- ReferenceNode
 187     \-BBBB
 188
 189   @ingroup NameSpaceApis
 190
 191   @param  [in]  ReferenceNode   Reference node.
 192                                 If a relative path is given, the
 193                                 search is done from this node. If
 194                                 an absolute path is given, the
 195                                 search is done from the root node.
 196                                 Must be a root node or an object
 197                                 node which is part of the
 198                                 namespace.
 199   @param  [in]  AslPath         ASL path to the searched node in
 200                                 the namespace. An ASL path name is
 201                                 NULL terminated. Can be a relative
 202                                 or absolute path.
 203                                 E.g.: "\\_SB.CLU0.CPU0" or "^CPU0"
 204   @param  [out] OutNode         Pointer to the found node.
 205                                 Contains NULL if not found.
 206
 207   @retval EFI_SUCCESS             The function completed successfully.
 208   @retval EFI_BUFFER_TOO_SMALL    No space left in the buffer.
 209   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 210   @retval EFI_OUT_OF_RESOURCES    Out of memory.
 211 **/
 212 EFI_STATUS
 213 EFIAPI
 214 AmlFindNode (
 215   IN  AML_NODE_HANDLE       ReferenceNode,
 216   IN  CHAR8               * AslPath,
 217   OUT AML_NODE_HANDLE     * OutNode
 218   );
 219
 220 /**
 221   @defgroup UserApis User APIs
 222   @{
 223     User APIs are implemented to ease most common actions that might be done
 224     using the AmlLib. They allow to find specific objects like "_UID" or
 225     "_CRS" and to update their value. It also shows what can be done using
 226     AmlLib functions.
 227   @}
 228 */
 229
 230 /** Update the name of a DeviceOp object node.
 231
 232   @ingroup UserApis
 233
 234   @param  [in] DeviceOpNode   Object node representing a Device.
 235                               Must have an OpCode=AML_NAME_OP, SubOpCode=0.
 236                               OpCode/SubOpCode.
 237                               DeviceOp object nodes are defined in ASL
 238                               using the "Device ()" function.
 239   @param  [in] NewNameString  The new Device's name.
 240                               Must be a NULL-terminated ASL NameString
 241                               e.g.: "DEV0", "DV15.DEV0", etc.
 242                               The input string is copied.
 243
 244   @retval EFI_SUCCESS             The function completed successfully.
 245   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 246 **/
 247 EFI_STATUS
 248 EFIAPI
 249 AmlDeviceOpUpdateName (
 250   IN  AML_OBJECT_NODE_HANDLE    DeviceOpNode,
 251   IN  CHAR8                   * NewNameString
 252   );
 253
 254 /** Update an integer value defined by a NameOp object node.
 255
 256   For compatibility reasons, the NameOpNode must initially
 257   contain an integer.
 258
 259   @ingroup UserApis
 260
 261   @param  [in] NameOpNode   NameOp object node.
 262                             Must have an OpCode=AML_NAME_OP, SubOpCode=0.
 263                             NameOp object nodes are defined in ASL
 264                             using the "Name ()" function.
 265   @param  [in] NewInt       New Integer value to assign.
 266                             Must be a UINT64.
 267
 268   @retval EFI_SUCCESS             The function completed successfully.
 269   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 270 **/
 271 EFI_STATUS
 272 EFIAPI
 273 AmlNameOpUpdateInteger (
 274   IN  AML_OBJECT_NODE_HANDLE  NameOpNode,
 275   IN  UINT64                  NewInt
 276   );
 277
 278 /** Update a string value defined by a NameOp object node.
 279
 280   The NameOpNode must initially contain a string.
 281   The EISAID ASL macro converts a string to an integer. This, it is
 282   not accepted.
 283
 284   @ingroup UserApis
 285
 286   @param  [in] NameOpNode   NameOp object node.
 287                             Must have an OpCode=AML_NAME_OP, SubOpCode=0.
 288                             NameOp object nodes are defined in ASL
 289                             using the "Name ()" function.
 290   @param  [in] NewName      New NULL terminated string to assign to
 291                             the NameOpNode.
 292                             The input string is copied.
 293
 294   @retval EFI_SUCCESS             The function completed successfully.
 295   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 296 **/
 297 EFI_STATUS
 298 EFIAPI
 299 AmlNameOpUpdateString (
 300   IN        AML_OBJECT_NODE_HANDLE    NameOpNode,
 301   IN  CONST CHAR8                   * NewName
 302   );
 303
 304 /** Get the first Resource Data element contained in a "_CRS" object.
 305
 306   In the following ASL code, the function will return the Resource Data
 307   node corresponding to the "QWordMemory ()" ASL macro.
 308   Name (_CRS, ResourceTemplate() {
 309       QWordMemory (...) {...},
 310       Interrupt (...) {...}
 311     }
 312   )
 313
 314   Note:
 315    - The "_CRS" object must be declared using ASL "Name (Declare Named Object)".
 316    - "_CRS" declared using ASL "Method (Declare Control Method)" is not
 317      supported.
 318
 319   @ingroup UserApis
 320
 321   @param  [in] NameOpCrsNode  NameOp object node defining a "_CRS" object.
 322                               Must have an OpCode=AML_NAME_OP, SubOpCode=0.
 323                               NameOp object nodes are defined in ASL
 324                               using the "Name ()" function.
 325   @param  [out] OutRdNode     Pointer to the first Resource Data element of
 326                               the "_CRS" object. A Resource Data element
 327                               is stored in a data node.
 328
 329   @retval EFI_SUCCESS             The function completed successfully.
 330   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 331 **/
 332 EFI_STATUS
 333 EFIAPI
 334 AmlNameOpCrsGetFirstRdNode (
 335   IN  AML_OBJECT_NODE_HANDLE   NameOpCrsNode,
 336   OUT AML_DATA_NODE_HANDLE   * OutRdNode
 337   );
 338
 339 /** Get the Resource Data element following the CurrRdNode Resource Data.
 340
 341   In the following ASL code, if CurrRdNode corresponds to the first
 342   "QWordMemory ()" ASL macro, the function will return the Resource Data
 343   node corresponding to the "Interrupt ()" ASL macro.
 344   Name (_CRS, ResourceTemplate() {
 345       QwordMemory (...) {...},
 346       Interrupt (...) {...}
 347     }
 348   )
 349
 350   The CurrRdNode Resource Data node must be defined in an object named "_CRS"
 351   and defined by a "Name ()" ASL function.
 352
 353   @ingroup UserApis
 354
 355   @param  [in]  CurrRdNode   Pointer to the current Resource Data element of
 356                              the "_CRS" variable.
 357   @param  [out] OutRdNode    Pointer to the Resource Data element following
 358                              the CurrRdNode.
 359                              Contain a NULL pointer if CurrRdNode is the
 360                              last Resource Data element in the list.
 361                              The "End Tag" is not considered as a resource
 362                              data element and is not returned.
 363
 364   @retval EFI_SUCCESS             The function completed successfully.
 365   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 366 **/
 367 EFI_STATUS
 368 EFIAPI
 369 AmlNameOpCrsGetNextRdNode (
 370   IN  AML_DATA_NODE_HANDLE    CurrRdNode,
 371   OUT AML_DATA_NODE_HANDLE  * OutRdNode
 372   );
 373
 374 /** Update the first interrupt of an Interrupt resource data node.
 375
 376   The flags of the Interrupt resource data are left unchanged.
 377
 378   The InterruptRdNode corresponds to the Resource Data created by the
 379   "Interrupt ()" ASL macro. It is an Extended Interrupt Resource Data.
 380   See ACPI 6.3 specification, s6.4.3.6 "Extended Interrupt Descriptor"
 381   for more information about Extended Interrupt Resource Data.
 382
 383   @ingroup UserApis
 384
 385   @param  [in]  InterruptRdNode   Pointer to the an extended interrupt
 386                                   resource data node.
 387   @param  [in]  Irq               Interrupt value to update.
 388
 389   @retval  EFI_SUCCESS            The function completed successfully.
 390   @retval  EFI_INVALID_PARAMETER  Invalid parameter.
 391   @retval  EFI_OUT_OF_RESOURCES   Out of resources.
 392 **/
 393 EFI_STATUS
 394 EFIAPI
 395 AmlUpdateRdInterrupt (
 396   IN  AML_DATA_NODE_HANDLE    InterruptRdNode,
 397   IN  UINT32                  Irq
 398   );
 399
 400 /** Update the base address and length of a QWord resource data node.
 401
 402   @ingroup UserApis
 403
 404   @param  [in] QWordRdNode         Pointer a QWord resource data
 405                                    node.
 406   @param  [in] BaseAddress         Base address.
 407   @param  [in] BaseAddressLength   Base address length.
 408
 409   @retval  EFI_SUCCESS            The function completed successfully.
 410   @retval  EFI_INVALID_PARAMETER  Invalid parameter.
 411   @retval  EFI_OUT_OF_RESOURCES   Out of resources.
 412 **/
 413 EFI_STATUS
 414 EFIAPI
 415 AmlUpdateRdQWord (
 416   IN  AML_DATA_NODE_HANDLE  QWordRdNode,
 417   IN  UINT64                BaseAddress,
 418   IN  UINT64                BaseAddressLength
 419   );
 420
 421 /** Add an Interrupt Resource Data node.
 422
 423   This function creates a Resource Data element corresponding to the
 424   "Interrupt ()" ASL function, stores it in an AML Data Node.
 425
 426   It then adds it after the input CurrRdNode in the list of resource data
 427   element.
 428
 429   The Resource Data effectively created is an Extended Interrupt Resource
 430   Data. See ACPI 6.3 specification, s6.4.3.6 "Extended Interrupt Descriptor"
 431   for more information about Extended Interrupt Resource Data.
 432
 433   The Extended Interrupt contains one single interrupt.
 434
 435   This function allocates memory to create a data node. It is the caller's
 436   responsibility to either:
 437    - attach this node to an AML tree;
 438    - delete this node.
 439
 440   Note: The _CRS node must be defined using the ASL Name () function.
 441         e.g. Name (_CRS, ResourceTemplate () {
 442                ...
 443              }
 444
 445   @ingroup UserApis
 446
 447   @param  [in]  NameOpCrsNode    NameOp object node defining a "_CRS" object.
 448                                  Must have an OpCode=AML_NAME_OP, SubOpCode=0.
 449                                  NameOp object nodes are defined in ASL
 450                                  using the "Name ()" function.
 451   @param  [in]  ResourceConsumer The device consumes the specified interrupt
 452                                  or produces it for use by a child device.
 453   @param  [in]  EdgeTriggered    The interrupt is edge triggered or
 454                                  level triggered.
 455   @param  [in]  ActiveLow        The interrupt is active-high or active-low.
 456   @param  [in]  Shared           The interrupt can be shared with other
 457                                  devices or not (Exclusive).
 458   @param  [in]  IrqList          Interrupt list. Must be non-NULL.
 459   @param  [in]  IrqCount         Interrupt count. Must be non-zero.
 460
 461
 462   @retval EFI_SUCCESS             The function completed successfully.
 463   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 464   @retval EFI_OUT_OF_RESOURCES    Could not allocate memory.
 465 **/
 466 EFI_STATUS
 467 EFIAPI
 468 AmlCodeGenCrsAddRdInterrupt (
 469   IN  AML_OBJECT_NODE_HANDLE  NameOpCrsNode,
 470   IN  BOOLEAN                 ResourceConsumer,
 471   IN  BOOLEAN                 EdgeTriggered,
 472   IN  BOOLEAN                 ActiveLow,
 473   IN  BOOLEAN                 Shared,
 474   IN  UINT32                * IrqList,
 475   IN  UINT8                   IrqCount
 476   );
 477
 478 /** AML code generation for DefinitionBlock.
 479
 480   Create a Root Node handle.
 481   It is the caller's responsibility to free the allocated memory
 482   with the AmlDeleteTree function.
 483
 484   AmlCodeGenDefinitionBlock (TableSignature, OemId, TableID, OEMRevision) is
 485   equivalent to the following ASL code:
 486     DefinitionBlock (AMLFileName, TableSignature, ComplianceRevision,
 487       OemId, TableID, OEMRevision) {}
 488   with the ComplianceRevision set to 2 and the AMLFileName is ignored.
 489
 490   @ingroup CodeGenApis
 491
 492   @param[in]  TableSignature       4-character ACPI signature.
 493                                    Must be 'DSDT' or 'SSDT'.
 494   @param[in]  OemId                6-character string OEM identifier.
 495   @param[in]  OemTableId           8-character string OEM table identifier.
 496   @param[in]  OemRevision          OEM revision number.
 497   @param[out] DefinitionBlockTerm  The ASL Term handle representing a
 498                                    Definition Block.
 499
 500   @retval EFI_SUCCESS             Success.
 501   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 502   @retval EFI_OUT_OF_RESOURCES    Failed to allocate memory.
 503 **/
 504 EFI_STATUS
 505 EFIAPI
 506 AmlCodeGenDefinitionBlock (
 507   IN  CONST CHAR8                 * TableSignature,
 508   IN  CONST CHAR8                 * OemId,
 509   IN  CONST CHAR8                 * OemTableId,
 510   IN        UINT32                  OemRevision,
 511   OUT       AML_ROOT_NODE_HANDLE  * NewRootNode
 512   );
 513
 514 /** AML code generation for a Name object node, containing a String.
 515
 516   AmlCodeGenNameString ("_HID", "HID0000", ParentNode, NewObjectNode) is
 517   equivalent of the following ASL code:
 518     Name(_HID, "HID0000")
 519
 520   @ingroup CodeGenApis
 521
 522   @param  [in] NameString     The new variable name.
 523                               Must be a NULL-terminated ASL NameString
 524                               e.g.: "DEV0", "DV15.DEV0", etc.
 525                               The input string is copied.
 526   @param [in]  String         NULL terminated String to associate to the
 527                               NameString.
 528   @param [in]  ParentNode     If provided, set ParentNode as the parent
 529                               of the node created.
 530   @param [out] NewObjectNode  If success, contains the created node.
 531
 532   @retval EFI_SUCCESS             Success.
 533   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 534   @retval EFI_OUT_OF_RESOURCES    Failed to allocate memory.
 535 **/
 536 EFI_STATUS
 537 EFIAPI
 538 AmlCodeGenNameString (
 539   IN  CONST CHAR8                   * NameString,
 540   IN        CHAR8                   * String,
 541   IN        AML_NODE_HANDLE           ParentNode,     OPTIONAL
 542   OUT       AML_OBJECT_NODE_HANDLE  * NewObjectNode   OPTIONAL
 543   );
 544
 545 /** AML code generation for a Name object node, containing an Integer.
 546
 547   AmlCodeGenNameInteger ("_UID", 1, ParentNode, NewObjectNode) is
 548   equivalent of the following ASL code:
 549     Name(_UID, One)
 550
 551   @ingroup CodeGenApis
 552
 553   @param  [in] NameString     The new variable name.
 554                               Must be a NULL-terminated ASL NameString
 555                               e.g.: "DEV0", "DV15.DEV0", etc.
 556                               The input string is copied.
 557   @param [in]  Integer        Integer to associate to the NameString.
 558   @param [in]  ParentNode     If provided, set ParentNode as the parent
 559                               of the node created.
 560   @param [out] NewObjectNode  If success, contains the created node.
 561
 562   @retval EFI_SUCCESS             Success.
 563   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 564   @retval EFI_OUT_OF_RESOURCES    Failed to allocate memory.
 565 **/
 566 EFI_STATUS
 567 EFIAPI
 568 AmlCodeGenNameInteger (
 569   IN  CONST CHAR8                   * NameString,
 570   IN        UINT64                    Integer,
 571   IN        AML_NODE_HANDLE           ParentNode,     OPTIONAL
 572   OUT       AML_OBJECT_NODE_HANDLE  * NewObjectNode   OPTIONAL
 573   );
 574
 575 /** AML code generation for a Device object node.
 576
 577   AmlCodeGenDevice ("COM0", ParentNode, NewObjectNode) is
 578   equivalent of the following ASL code:
 579     Device(COM0) {}
 580
 581   @ingroup CodeGenApis
 582
 583   @param  [in] NameString     The new Device's name.
 584                               Must be a NULL-terminated ASL NameString
 585                               e.g.: "DEV0", "DV15.DEV0", etc.
 586                               The input string is copied.
 587   @param [in]  ParentNode     If provided, set ParentNode as the parent
 588                               of the node created.
 589   @param [out] NewObjectNode  If success, contains the created node.
 590
 591   @retval EFI_SUCCESS             Success.
 592   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 593   @retval EFI_OUT_OF_RESOURCES    Failed to allocate memory.
 594 **/
 595 EFI_STATUS
 596 EFIAPI
 597 AmlCodeGenDevice (
 598   IN  CONST CHAR8                   * NameString,
 599   IN        AML_NODE_HANDLE           ParentNode,     OPTIONAL
 600   OUT       AML_OBJECT_NODE_HANDLE  * NewObjectNode   OPTIONAL
 601   );
 602
 603 /** AML code generation for a Scope object node.
 604
 605   AmlCodeGenScope ("_SB", ParentNode, NewObjectNode) is
 606   equivalent of the following ASL code:
 607     Scope(_SB) {}
 608
 609   @ingroup CodeGenApis
 610
 611   @param  [in] NameString     The new Scope's name.
 612                               Must be a NULL-terminated ASL NameString
 613                               e.g.: "DEV0", "DV15.DEV0", etc.
 614                               The input string is copied.
 615   @param [in]  ParentNode     If provided, set ParentNode as the parent
 616                               of the node created.
 617   @param [out] NewObjectNode  If success, contains the created node.
 618
 619   @retval EFI_SUCCESS             Success.
 620   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 621   @retval EFI_OUT_OF_RESOURCES    Failed to allocate memory.
 622 **/
 623 EFI_STATUS
 624 EFIAPI
 625 AmlCodeGenScope (
 626   IN  CONST CHAR8                   * NameString,
 627   IN        AML_NODE_HANDLE           ParentNode,     OPTIONAL
 628   OUT       AML_OBJECT_NODE_HANDLE  * NewObjectNode   OPTIONAL
 629   );
 630
 631 #endif // AML_LIB_H_