DynamicTablesPkg/Library/Common/AmlLib/CodeGen/AmlCodeGen.c

   1 /** @file
   2   AML Code Generation.
   3
   4   Copyright (c) 2020 - 2021, Arm Limited. All rights reserved.<BR>
   5
   6   SPDX-License-Identifier: BSD-2-Clause-Patent
   7 **/
   8
   9 #include <AmlNodeDefines.h>
  10
  11 #include <AcpiTableGenerator.h>
  12
  13 #include <AmlCoreInterface.h>
  14 #include <AmlEncoding/Aml.h>
  15 #include <Tree/AmlNode.h>
  16 #include <Tree/AmlTree.h>
  17 #include <String/AmlString.h>
  18 #include <Utils/AmlUtility.h>
  19
  20 /** Utility function to link a node when returning from a CodeGen function.
  21
  22   @param [in]  Node           Newly created node.
  23   @param [in]  ParentNode     If provided, set ParentNode as the parent
  24                               of the node created.
  25   @param [out] NewObjectNode  If not NULL:
  26                                - and Success, contains the created Node.
  27                                - and Error, reset to NULL.
  28
  29   @retval  EFI_SUCCESS            The function completed successfully.
  30   @retval  EFI_INVALID_PARAMETER  Invalid parameter.
  31 **/
  32 STATIC
  33 EFI_STATUS
  34 EFIAPI
  35 LinkNode (
  36   IN  AML_OBJECT_NODE    * Node,
  37   IN  AML_NODE_HEADER    * ParentNode,
  38   OUT AML_OBJECT_NODE   ** NewObjectNode
  39   )
  40 {
  41   EFI_STATUS    Status;
  42
  43   if (NewObjectNode != NULL) {
  44     *NewObjectNode = NULL;
  45   }
  46
  47   // Add RdNode as the last element.
  48   if (ParentNode != NULL) {
  49     Status = AmlVarListAddTail (ParentNode, (AML_NODE_HEADER*)Node);
  50     if (EFI_ERROR (Status)) {
  51       ASSERT (0);
  52       return Status;
  53     }
  54   }
  55
  56   if (NewObjectNode != NULL) {
  57     *NewObjectNode = Node;
  58   }
  59
  60   return EFI_SUCCESS;
  61 }
  62
  63 /** AML code generation for DefinitionBlock.
  64
  65   Create a Root Node handle.
  66   It is the caller's responsibility to free the allocated memory
  67   with the AmlDeleteTree function.
  68
  69   AmlCodeGenDefinitionBlock (TableSignature, OemID, TableID, OEMRevision) is
  70   equivalent to the following ASL code:
  71     DefinitionBlock (AMLFileName, TableSignature, ComplianceRevision,
  72       OemID, TableID, OEMRevision) {}
  73   with the ComplianceRevision set to 2 and the AMLFileName is ignored.
  74
  75   @param[in]  TableSignature       4-character ACPI signature.
  76                                    Must be 'DSDT' or 'SSDT'.
  77   @param[in]  OemId                6-character string OEM identifier.
  78   @param[in]  OemTableId           8-character string OEM table identifier.
  79   @param[in]  OemRevision          OEM revision number.
  80   @param[out] NewRootNode          Pointer to the root node representing a
  81                                    Definition Block.
  82
  83   @retval EFI_SUCCESS             Success.
  84   @retval EFI_INVALID_PARAMETER   Invalid parameter.
  85   @retval EFI_OUT_OF_RESOURCES    Failed to allocate memory.
  86 **/
  87 EFI_STATUS
  88 EFIAPI
  89 AmlCodeGenDefinitionBlock (
  90   IN  CONST CHAR8             * TableSignature,
  91   IN  CONST CHAR8             * OemId,
  92   IN  CONST CHAR8             * OemTableId,
  93   IN        UINT32              OemRevision,
  94   OUT       AML_ROOT_NODE    ** NewRootNode
  95   )
  96 {
  97   EFI_STATUS                      Status;
  98   EFI_ACPI_DESCRIPTION_HEADER     AcpiHeader;
  99
 100   if ((TableSignature == NULL)  ||
 101       (OemId == NULL)           ||
 102       (OemTableId == NULL)      ||
 103       (NewRootNode == NULL)) {
 104     ASSERT (0);
 105     return EFI_INVALID_PARAMETER;
 106   }
 107
 108   CopyMem (&AcpiHeader.Signature, TableSignature, 4);
 109   AcpiHeader.Length = sizeof (EFI_ACPI_DESCRIPTION_HEADER);
 110   AcpiHeader.Revision = 2;
 111   CopyMem (&AcpiHeader.OemId, OemId, 6);
 112   CopyMem (&AcpiHeader.OemTableId, OemTableId, 8);
 113   AcpiHeader.OemRevision = OemRevision;
 114   AcpiHeader.CreatorId = TABLE_GENERATOR_CREATOR_ID_ARM;
 115   AcpiHeader.CreatorRevision = CREATE_REVISION (1, 0);
 116
 117   Status = AmlCreateRootNode (&AcpiHeader, NewRootNode);
 118   ASSERT_EFI_ERROR (Status);
 119
 120   return Status;
 121 }
 122
 123 /** AML code generation for a String object node.
 124
 125   @param [in]  String          Pointer to a NULL terminated string.
 126   @param [out] NewObjectNode   If success, contains the created
 127                                String object node.
 128
 129   @retval EFI_SUCCESS             Success.
 130   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 131   @retval EFI_OUT_OF_RESOURCES    Failed to allocate memory.
 132 **/
 133 STATIC
 134 EFI_STATUS
 135 EFIAPI
 136 AmlCodeGenString (
 137   IN  CHAR8               * String,
 138   OUT AML_OBJECT_NODE    ** NewObjectNode
 139   )
 140 {
 141   EFI_STATUS          Status;
 142   AML_OBJECT_NODE   * ObjectNode;
 143   AML_DATA_NODE     * DataNode;
 144
 145   if ((String == NULL)  ||
 146       (NewObjectNode == NULL)) {
 147     ASSERT (0);
 148     return EFI_INVALID_PARAMETER;
 149   }
 150
 151   DataNode = NULL;
 152
 153   Status = AmlCreateObjectNode (
 154              AmlGetByteEncodingByOpCode (AML_STRING_PREFIX, 0),
 155              0,
 156              &ObjectNode
 157              );
 158   if (EFI_ERROR (Status)) {
 159     ASSERT (0);
 160     return Status;
 161   }
 162
 163   Status = AmlCreateDataNode (
 164              EAmlNodeDataTypeString,
 165              (UINT8*)String,
 166              (UINT32)AsciiStrLen (String) + 1,
 167              &DataNode
 168              );
 169   if (EFI_ERROR (Status)) {
 170     ASSERT (0);
 171     goto error_handler;
 172   }
 173
 174   Status = AmlSetFixedArgument (
 175              ObjectNode,
 176              EAmlParseIndexTerm0,
 177              (AML_NODE_HEADER*)DataNode
 178              );
 179   if (EFI_ERROR (Status)) {
 180     ASSERT (0);
 181     AmlDeleteTree ((AML_NODE_HEADER*)DataNode);
 182     goto error_handler;
 183   }
 184
 185   *NewObjectNode = ObjectNode;
 186   return Status;
 187
 188 error_handler:
 189   AmlDeleteTree ((AML_NODE_HEADER*)ObjectNode);
 190   return Status;
 191 }
 192
 193 /** AML code generation for an Integer object node.
 194
 195   @param [in]  Integer         Integer of the Integer object node.
 196   @param [out] NewObjectNode   If success, contains the created
 197                                Integer object node.
 198
 199   @retval EFI_SUCCESS             Success.
 200   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 201   @retval EFI_OUT_OF_RESOURCES    Failed to allocate memory.
 202 **/
 203 STATIC
 204 EFI_STATUS
 205 EFIAPI
 206 AmlCodeGenInteger (
 207   IN  UINT64                Integer,
 208   OUT AML_OBJECT_NODE    ** NewObjectNode
 209   )
 210 {
 211   EFI_STATUS          Status;
 212   INT8                ValueWidthDiff;
 213
 214   if (NewObjectNode == NULL) {
 215     ASSERT (0);
 216     return EFI_INVALID_PARAMETER;
 217   }
 218
 219    // Create an object node containing Zero.
 220    Status = AmlCreateObjectNode (
 221              AmlGetByteEncodingByOpCode (AML_ZERO_OP, 0),
 222              0,
 223              NewObjectNode
 224              );
 225   if (EFI_ERROR (Status)) {
 226     ASSERT (0);
 227     return Status;
 228   }
 229
 230   // Update the object node with integer value.
 231   Status = AmlNodeSetIntegerValue (*NewObjectNode, Integer, &ValueWidthDiff);
 232   if (EFI_ERROR (Status)) {
 233     ASSERT (0);
 234     AmlDeleteTree ((AML_NODE_HEADER*)*NewObjectNode);
 235   }
 236
 237   return Status;
 238 }
 239
 240 /** AML code generation for a Package object node.
 241
 242   The package generated is empty. New elements can be added via its
 243   list of variable arguments.
 244
 245   @param [out] NewObjectNode   If success, contains the created
 246                                Package object node.
 247
 248   @retval EFI_SUCCESS             Success.
 249   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 250   @retval EFI_OUT_OF_RESOURCES    Failed to allocate memory.
 251 **/
 252 STATIC
 253 EFI_STATUS
 254 EFIAPI
 255 AmlCodeGenPackage (
 256   OUT AML_OBJECT_NODE    ** NewObjectNode
 257   )
 258 {
 259   EFI_STATUS        Status;
 260   AML_DATA_NODE   * DataNode;
 261   UINT8             NodeCount;
 262
 263   if (NewObjectNode == NULL) {
 264     ASSERT (0);
 265     return EFI_INVALID_PARAMETER;
 266   }
 267
 268   NodeCount = 0;
 269
 270   // Create an object node.
 271   // PkgLen is 2:
 272   //  - one byte to store the PkgLength
 273   //  - one byte for the NumElements.
 274   // Cf ACPI6.3, s20.2.5 "Term Objects Encoding"
 275   // DefPackage  := PackageOp PkgLength NumElements PackageElementList
 276   // NumElements := ByteData
 277   Status = AmlCreateObjectNode (
 278              AmlGetByteEncodingByOpCode (AML_PACKAGE_OP, 0),
 279              2,
 280              NewObjectNode
 281              );
 282   if (EFI_ERROR (Status)) {
 283     ASSERT (0);
 284     return Status;
 285   }
 286
 287   // NumElements is a ByteData.
 288   Status = AmlCreateDataNode (
 289              EAmlNodeDataTypeUInt,
 290              &NodeCount,
 291              sizeof (NodeCount),
 292              &DataNode
 293              );
 294   if (EFI_ERROR (Status)) {
 295     ASSERT (0);
 296     goto error_handler;
 297   }
 298
 299   Status = AmlSetFixedArgument (
 300              *NewObjectNode,
 301              EAmlParseIndexTerm0,
 302              (AML_NODE_HEADER*)DataNode
 303              );
 304   if (EFI_ERROR (Status)) {
 305     ASSERT (0);
 306     goto error_handler;
 307   }
 308
 309   return Status;
 310
 311 error_handler:
 312   AmlDeleteTree ((AML_NODE_HEADER*)*NewObjectNode);
 313   if (DataNode != NULL) {
 314     AmlDeleteTree ((AML_NODE_HEADER*)DataNode);
 315   }
 316   return Status;
 317 }
 318
 319 /** AML code generation for a Name object node.
 320
 321   @param  [in] NameString     The new variable name.
 322                               Must be a NULL-terminated ASL NameString
 323                               e.g.: "DEV0", "DV15.DEV0", etc.
 324                               This input string is copied.
 325   @param [in]  Object         Object associated to the NameString.
 326   @param [in]  ParentNode     If provided, set ParentNode as the parent
 327                               of the node created.
 328   @param [out] NewObjectNode  If success, contains the created node.
 329
 330   @retval EFI_SUCCESS             Success.
 331   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 332   @retval EFI_OUT_OF_RESOURCES    Failed to allocate memory.
 333 **/
 334 STATIC
 335 EFI_STATUS
 336 EFIAPI
 337 AmlCodeGenName (
 338   IN  CONST CHAR8              * NameString,
 339   IN        AML_OBJECT_NODE    * Object,
 340   IN        AML_NODE_HEADER    * ParentNode,     OPTIONAL
 341   OUT       AML_OBJECT_NODE   ** NewObjectNode   OPTIONAL
 342   )
 343 {
 344   EFI_STATUS          Status;
 345   AML_OBJECT_NODE   * ObjectNode;
 346   AML_DATA_NODE     * DataNode;
 347   CHAR8             * AmlNameString;
 348   UINT32              AmlNameStringSize;
 349
 350   if ((NameString == NULL)    ||
 351       (Object == NULL)        ||
 352       ((ParentNode == NULL) && (NewObjectNode == NULL))) {
 353     ASSERT (0);
 354     return EFI_INVALID_PARAMETER;
 355   }
 356
 357   ObjectNode = NULL;
 358   DataNode = NULL;
 359   AmlNameString = NULL;
 360
 361   Status = ConvertAslNameToAmlName (NameString, &AmlNameString);
 362   if (EFI_ERROR (Status)) {
 363     ASSERT (0);
 364     return Status;
 365   }
 366
 367   Status = AmlGetNameStringSize (AmlNameString, &AmlNameStringSize);
 368   if (EFI_ERROR (Status)) {
 369     ASSERT (0);
 370     goto error_handler1;
 371   }
 372
 373   Status = AmlCreateObjectNode (
 374              AmlGetByteEncodingByOpCode (AML_NAME_OP, 0),
 375              0,
 376              &ObjectNode
 377              );
 378   if (EFI_ERROR (Status)) {
 379     ASSERT (0);
 380     goto error_handler1;
 381   }
 382
 383   Status = AmlCreateDataNode (
 384              EAmlNodeDataTypeNameString,
 385              (UINT8*)AmlNameString,
 386              AmlNameStringSize,
 387              &DataNode
 388              );
 389   if (EFI_ERROR (Status)) {
 390     ASSERT (0);
 391     goto error_handler2;
 392   }
 393
 394   Status = AmlSetFixedArgument (
 395              ObjectNode,
 396              EAmlParseIndexTerm0,
 397              (AML_NODE_HEADER*)DataNode
 398              );
 399   if (EFI_ERROR (Status)) {
 400     ASSERT (0);
 401     AmlDeleteTree ((AML_NODE_HEADER*)DataNode);
 402     goto error_handler2;
 403   }
 404
 405   Status = AmlSetFixedArgument (
 406              ObjectNode,
 407              EAmlParseIndexTerm1,
 408              (AML_NODE_HEADER*)Object
 409              );
 410   if (EFI_ERROR (Status)) {
 411     ASSERT (0);
 412     goto error_handler2;
 413   }
 414
 415   Status = LinkNode (
 416              ObjectNode,
 417              ParentNode,
 418              NewObjectNode
 419              );
 420   if (EFI_ERROR (Status)) {
 421     ASSERT (0);
 422     goto error_handler2;
 423   }
 424
 425   // Free AmlNameString before returning as it is copied
 426   // in the call to AmlCreateDataNode().
 427   goto error_handler1;
 428
 429 error_handler2:
 430   if (ObjectNode != NULL) {
 431     AmlDeleteTree ((AML_NODE_HEADER*)ObjectNode);
 432   }
 433
 434 error_handler1:
 435   if (AmlNameString != NULL) {
 436     FreePool (AmlNameString);
 437   }
 438
 439   return Status;
 440 }
 441
 442 /** AML code generation for a Name object node, containing a String.
 443
 444   AmlCodeGenNameString ("_HID", "HID0000", ParentNode, NewObjectNode) is
 445   equivalent of the following ASL code:
 446     Name(_HID, "HID0000")
 447
 448   @param  [in] NameString     The new variable name.
 449                               Must be a NULL-terminated ASL NameString
 450                               e.g.: "DEV0", "DV15.DEV0", etc.
 451                               The input string is copied.
 452   @param [in]  String         NULL terminated String to associate to the
 453                               NameString.
 454   @param [in]  ParentNode     If provided, set ParentNode as the parent
 455                               of the node created.
 456   @param [out] NewObjectNode  If success, contains the created node.
 457
 458   @retval EFI_SUCCESS             Success.
 459   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 460   @retval EFI_OUT_OF_RESOURCES    Failed to allocate memory.
 461 **/
 462 EFI_STATUS
 463 EFIAPI
 464 AmlCodeGenNameString (
 465   IN  CONST CHAR8              * NameString,
 466   IN        CHAR8              * String,
 467   IN        AML_NODE_HEADER    * ParentNode,     OPTIONAL
 468   OUT       AML_OBJECT_NODE   ** NewObjectNode   OPTIONAL
 469   )
 470 {
 471   EFI_STATUS          Status;
 472   AML_OBJECT_NODE   * ObjectNode;
 473
 474   if ((NameString == NULL)  ||
 475       (String == NULL)      ||
 476       ((ParentNode == NULL) && (NewObjectNode == NULL))) {
 477     ASSERT (0);
 478     return EFI_INVALID_PARAMETER;
 479   }
 480
 481   Status = AmlCodeGenString (String, &ObjectNode);
 482   if (EFI_ERROR (Status)) {
 483     ASSERT (0);
 484     return Status;
 485   }
 486
 487   Status = AmlCodeGenName (
 488              NameString,
 489              ObjectNode,
 490              ParentNode,
 491              NewObjectNode
 492              );
 493   if (EFI_ERROR (Status)) {
 494     ASSERT (0);
 495     AmlDeleteTree ((AML_NODE_HEADER*)ObjectNode);
 496   }
 497
 498   return Status;
 499 }
 500
 501 /** AML code generation for a Name object node, containing an Integer.
 502
 503   AmlCodeGenNameInteger ("_UID", 1, ParentNode, NewObjectNode) is
 504   equivalent of the following ASL code:
 505     Name(_UID, One)
 506
 507   @param  [in] NameString     The new variable name.
 508                               Must be a NULL-terminated ASL NameString
 509                               e.g.: "DEV0", "DV15.DEV0", etc.
 510                               The input string is copied.
 511   @param [in]  Integer        Integer to associate to the NameString.
 512   @param [in]  ParentNode     If provided, set ParentNode as the parent
 513                               of the node created.
 514   @param [out] NewObjectNode  If success, contains the created node.
 515
 516   @retval EFI_SUCCESS             Success.
 517   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 518   @retval EFI_OUT_OF_RESOURCES    Failed to allocate memory.
 519 **/
 520 EFI_STATUS
 521 EFIAPI
 522 AmlCodeGenNameInteger (
 523   IN  CONST CHAR8              * NameString,
 524   IN        UINT64               Integer,
 525   IN        AML_NODE_HEADER    * ParentNode,     OPTIONAL
 526   OUT       AML_OBJECT_NODE   ** NewObjectNode   OPTIONAL
 527   )
 528 {
 529   EFI_STATUS          Status;
 530   AML_OBJECT_NODE   * ObjectNode;
 531
 532   if ((NameString == NULL)  ||
 533       ((ParentNode == NULL) && (NewObjectNode == NULL))) {
 534     ASSERT (0);
 535     return EFI_INVALID_PARAMETER;
 536   }
 537
 538   Status = AmlCodeGenInteger (Integer, &ObjectNode);
 539   if (EFI_ERROR (Status)) {
 540     ASSERT (0);
 541     return Status;
 542   }
 543
 544   Status = AmlCodeGenName (
 545              NameString,
 546              ObjectNode,
 547              ParentNode,
 548              NewObjectNode
 549              );
 550   if (EFI_ERROR (Status)) {
 551     ASSERT (0);
 552     AmlDeleteTree ((AML_NODE_HEADER*)ObjectNode);
 553   }
 554
 555   return Status;
 556 }
 557
 558 /** AML code generation for a Device object node.
 559
 560   AmlCodeGenDevice ("COM0", ParentNode, NewObjectNode) is
 561   equivalent of the following ASL code:
 562     Device(COM0) {}
 563
 564   @param  [in] NameString     The new Device's name.
 565                               Must be a NULL-terminated ASL NameString
 566                               e.g.: "DEV0", "DV15.DEV0", etc.
 567                               The input string is copied.
 568   @param [in]  ParentNode     If provided, set ParentNode as the parent
 569                               of the node created.
 570   @param [out] NewObjectNode  If success, contains the created node.
 571
 572   @retval EFI_SUCCESS             Success.
 573   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 574   @retval EFI_OUT_OF_RESOURCES    Failed to allocate memory.
 575 **/
 576 EFI_STATUS
 577 EFIAPI
 578 AmlCodeGenDevice (
 579   IN  CONST CHAR8              * NameString,
 580   IN        AML_NODE_HEADER    * ParentNode,     OPTIONAL
 581   OUT       AML_OBJECT_NODE   ** NewObjectNode   OPTIONAL
 582   )
 583 {
 584   EFI_STATUS          Status;
 585   AML_OBJECT_NODE   * ObjectNode;
 586   AML_DATA_NODE     * DataNode;
 587   CHAR8             * AmlNameString;
 588   UINT32              AmlNameStringSize;
 589
 590   if ((NameString == NULL)  ||
 591       ((ParentNode == NULL) && (NewObjectNode == NULL))) {
 592     ASSERT (0);
 593     return EFI_INVALID_PARAMETER;
 594   }
 595
 596   ObjectNode = NULL;
 597   DataNode = NULL;
 598   AmlNameString = NULL;
 599
 600   Status = ConvertAslNameToAmlName (NameString, &AmlNameString);
 601   if (EFI_ERROR (Status)) {
 602     ASSERT (0);
 603     return Status;
 604   }
 605
 606   Status = AmlGetNameStringSize (AmlNameString, &AmlNameStringSize);
 607   if (EFI_ERROR (Status)) {
 608     ASSERT (0);
 609     goto error_handler1;
 610   }
 611
 612   Status = AmlCreateObjectNode (
 613              AmlGetByteEncodingByOpCode (AML_EXT_OP, AML_EXT_DEVICE_OP),
 614              AmlNameStringSize + AmlComputePkgLengthWidth (AmlNameStringSize),
 615              &ObjectNode
 616              );
 617   if (EFI_ERROR (Status)) {
 618     ASSERT (0);
 619     goto error_handler1;
 620   }
 621
 622   Status = AmlCreateDataNode (
 623              EAmlNodeDataTypeNameString,
 624              (UINT8*)AmlNameString,
 625              AmlNameStringSize,
 626              &DataNode
 627              );
 628   if (EFI_ERROR (Status)) {
 629     ASSERT (0);
 630     goto error_handler2;
 631   }
 632
 633   Status = AmlSetFixedArgument (
 634              ObjectNode,
 635              EAmlParseIndexTerm0,
 636              (AML_NODE_HEADER*)DataNode
 637              );
 638   if (EFI_ERROR (Status)) {
 639     ASSERT (0);
 640     AmlDeleteTree ((AML_NODE_HEADER*)DataNode);
 641     goto error_handler2;
 642   }
 643
 644   Status = LinkNode (
 645              ObjectNode,
 646              ParentNode,
 647              NewObjectNode
 648              );
 649   if (EFI_ERROR (Status)) {
 650     ASSERT (0);
 651     goto error_handler2;
 652   }
 653
 654   // Free AmlNameString before returning as it is copied
 655   // in the call to AmlCreateDataNode().
 656   goto error_handler1;
 657
 658 error_handler2:
 659   if (ObjectNode != NULL) {
 660     AmlDeleteTree ((AML_NODE_HEADER*)ObjectNode);
 661   }
 662
 663 error_handler1:
 664   if (AmlNameString != NULL) {
 665     FreePool (AmlNameString);
 666   }
 667
 668   return Status;
 669 }
 670
 671 /** AML code generation for a Scope object node.
 672
 673   AmlCodeGenScope ("_SB", ParentNode, NewObjectNode) is
 674   equivalent of the following ASL code:
 675     Scope(_SB) {}
 676
 677   @param  [in] NameString     The new Scope's name.
 678                               Must be a NULL-terminated ASL NameString
 679                               e.g.: "DEV0", "DV15.DEV0", etc.
 680                               The input string is copied.
 681   @param [in]  ParentNode     If provided, set ParentNode as the parent
 682                               of the node created.
 683   @param [out] NewObjectNode  If success, contains the created node.
 684
 685   @retval EFI_SUCCESS             Success.
 686   @retval EFI_INVALID_PARAMETER   Invalid parameter.
 687   @retval EFI_OUT_OF_RESOURCES    Failed to allocate memory.
 688 **/
 689 EFI_STATUS
 690 EFIAPI
 691 AmlCodeGenScope (
 692   IN  CONST CHAR8              * NameString,
 693   IN        AML_NODE_HEADER    * ParentNode,     OPTIONAL
 694   OUT       AML_OBJECT_NODE   ** NewObjectNode   OPTIONAL
 695   )
 696 {
 697   EFI_STATUS          Status;
 698   AML_OBJECT_NODE   * ObjectNode;
 699   AML_DATA_NODE     * DataNode;
 700   CHAR8             * AmlNameString;
 701   UINT32              AmlNameStringSize;
 702
 703   if ((NameString == NULL)  ||
 704       ((ParentNode == NULL) && (NewObjectNode == NULL))) {
 705     ASSERT (0);
 706     return EFI_INVALID_PARAMETER;
 707   }
 708
 709   ObjectNode = NULL;
 710   DataNode = NULL;
 711   AmlNameString = NULL;
 712
 713   Status = ConvertAslNameToAmlName (NameString, &AmlNameString);
 714   if (EFI_ERROR (Status)) {
 715     ASSERT (0);
 716     return Status;
 717   }
 718
 719   Status = AmlGetNameStringSize (AmlNameString, &AmlNameStringSize);
 720   if (EFI_ERROR (Status)) {
 721     ASSERT (0);
 722     goto error_handler1;
 723   }
 724
 725   Status = AmlCreateObjectNode (
 726              AmlGetByteEncodingByOpCode (AML_SCOPE_OP, 0),
 727              AmlNameStringSize + AmlComputePkgLengthWidth (AmlNameStringSize),
 728              &ObjectNode
 729              );
 730   if (EFI_ERROR (Status)) {
 731     ASSERT (0);
 732     goto error_handler1;
 733   }
 734
 735   Status = AmlCreateDataNode (
 736              EAmlNodeDataTypeNameString,
 737              (UINT8*)AmlNameString,
 738              AmlNameStringSize,
 739              &DataNode
 740              );
 741   if (EFI_ERROR (Status)) {
 742     ASSERT (0);
 743     goto error_handler2;
 744   }
 745
 746   Status = AmlSetFixedArgument (
 747              ObjectNode,
 748              EAmlParseIndexTerm0,
 749              (AML_NODE_HEADER*)DataNode
 750              );
 751   if (EFI_ERROR (Status)) {
 752     ASSERT (0);
 753     AmlDeleteTree ((AML_NODE_HEADER*)DataNode);
 754     goto error_handler2;
 755   }
 756
 757   Status = LinkNode (
 758              ObjectNode,
 759              ParentNode,
 760              NewObjectNode
 761              );
 762   if (EFI_ERROR (Status)) {
 763     ASSERT (0);
 764     goto error_handler2;
 765   }
 766
 767   // Free AmlNameString before returning as it is copied
 768   // in the call to AmlCreateDataNode().
 769   goto error_handler1;
 770
 771 error_handler2:
 772   if (ObjectNode != NULL) {
 773     AmlDeleteTree ((AML_NODE_HEADER*)ObjectNode);
 774   }
 775
 776 error_handler1:
 777   if (AmlNameString != NULL) {
 778     FreePool (AmlNameString);
 779   }
 780
 781   return Status;
 782 }