DynamicTablesPkg/Library/Common/AmlLib/Api/AmlApiHelper.c

   1 /** @file
   2   AML Helper.
   3
   4   Copyright (c) 2020, Arm Limited. All rights reserved.<BR>
   5
   6   SPDX-License-Identifier: BSD-2-Clause-Patent
   7 **/
   8
   9 /* Even though this file has access to the internal Node definition,
  10    i.e. AML_ROOT_NODE, AML_OBJECT_NODE, etc. Only the external node
  11    handle types should be used, i.e. AML_NODE_HANDLE, AML_ROOT_NODE_HANDLE,
  12    etc.
  13    Indeed, the functions in the "Api" folder should be implemented only
  14    using the "safe" functions available in the "Include" folder. This
  15    makes the functions available in the "Api" folder easy to export.
  16 */
  17 #include <Api/AmlApiHelper.h>
  18
  19 #include <AmlCoreInterface.h>
  20 #include <AmlInclude.h>
  21 #include <String/AmlString.h>
  22
  23 /** Compare the NameString defined by the "Name ()" ASL function,
  24     and stored in the NameOpNode, with the input NameString.
  25
  26   An ASL NameString is expected to be NULL terminated, and can be composed
  27   of NameSegs that have less that 4 chars, like "DEV". "DEV" will be expanded
  28   as "DEV_".
  29
  30   An AML NameString is not NULL terminated and is is only composed of
  31   4 chars long NameSegs.
  32
  33   @param  [in] NameOpNode   NameOp object node defining a variable.
  34                             Must have an AML_NAME_OP/0 OpCode/SubOpCode.
  35                             NameOp object nodes are defined in ASL
  36                             using the "Name ()" function.
  37   @param  [in] AslName      ASL NameString to compare the NameOp's name with.
  38                             Must be NULL terminated.
  39
  40   @retval TRUE If the AslName and the AmlName defined by the NameOp node
  41           are similar.
  42   @retval FALSE Otherwise.
  43 **/
  44 BOOLEAN
  45 EFIAPI
  46 AmlNameOpCompareName (
  47   IN  AML_OBJECT_NODE_HANDLE    NameOpNode,
  48   IN  CHAR8                   * AslName
  49   )
  50 {
  51   EFI_STATUS              Status;
  52   AML_DATA_NODE_HANDLE    NameDataNode;
  53
  54   CHAR8                 * AmlName;
  55   UINT32                  AmlNameSize;
  56
  57   BOOLEAN                 RetVal;
  58
  59   if ((NameOpNode == NULL)                                                ||
  60       (AmlGetNodeType ((AML_NODE_HANDLE)NameOpNode) != EAmlNodeObject)    ||
  61       (!AmlNodeHasOpCode (NameOpNode, AML_NAME_OP, 0))                    ||
  62       (AslName == NULL)) {
  63     ASSERT (0);
  64     return FALSE;
  65   }
  66
  67   // Get the NameOp name, being in a data node
  68   // which is the first fixed argument (i.e. index 0).
  69   NameDataNode = (AML_DATA_NODE_HANDLE)AmlGetFixedArgument (
  70                                          NameOpNode,
  71                                          EAmlParseIndexTerm0
  72                                          );
  73   if ((NameDataNode == NULL)                                            ||
  74       (AmlGetNodeType ((AML_NODE_HANDLE)NameDataNode) != EAmlNodeData)  ||
  75       (!AmlNodeHasDataType (NameDataNode, EAmlNodeDataTypeNameString))) {
  76     ASSERT (0);
  77     return FALSE;
  78   }
  79
  80   // Get the size of the name.
  81   Status = AmlGetDataNodeBuffer (NameDataNode, NULL, &AmlNameSize);
  82   if (EFI_ERROR (Status)) {
  83     ASSERT (0);
  84     return FALSE;
  85   }
  86
  87   // Allocate memory to fetch the name.
  88   AmlName = AllocateZeroPool (AmlNameSize);
  89   if (AmlName == NULL) {
  90     ASSERT (0);
  91     return FALSE;
  92   }
  93
  94   // Fetch the name.
  95   Status = AmlGetDataNodeBuffer (NameDataNode, (UINT8*)AmlName, &AmlNameSize);
  96   if (EFI_ERROR (Status)) {
  97     FreePool (AmlName);
  98     ASSERT (0);
  99     return FALSE;
 100   }
 101
 102   // Compare the input AslName and the AmlName stored in the NameOp node.
 103   RetVal = CompareAmlWithAslNameString (AmlName, AslName);
 104
 105   // Free the string buffer.
 106   FreePool (AmlName);
 107   return RetVal;
 108 }
 109
 110 /** Check whether ObjectNode has the input OpCode/SubOpcode couple.
 111
 112   @param  [in]  ObjectNode  Pointer to an object node.
 113   @param  [in]  OpCode      OpCode to check
 114   @param  [in]  SubOpCode   SubOpCode to check
 115
 116   @retval TRUE    The node is an object node and
 117                   the Opcode and SubOpCode match.
 118   @retval FALSE   Otherwise.
 119 **/
 120 BOOLEAN
 121 EFIAPI
 122 AmlNodeHasOpCode (
 123   IN  AML_OBJECT_NODE_HANDLE    ObjectNode,
 124   IN  UINT8                     OpCode,
 125   IN  UINT8                     SubOpCode
 126   )
 127 {
 128   EFI_STATUS    Status;
 129   UINT8         NodeOpCode;
 130   UINT8         NodeSubOpCode;
 131
 132   // Get the Node information.
 133   Status = AmlGetObjectNodeInfo (
 134              ObjectNode,
 135              &NodeOpCode,
 136              &NodeSubOpCode,
 137              NULL,
 138              NULL
 139              );
 140   if (EFI_ERROR (Status)) {
 141     ASSERT (0);
 142     return FALSE;
 143   }
 144
 145   // Check the OpCode and SubOpCode.
 146   if ((OpCode != NodeOpCode)  ||
 147       (SubOpCode != NodeSubOpCode)) {
 148     return FALSE;
 149   }
 150
 151   return TRUE;
 152 }
 153
 154 /** Check whether DataNode has the input DataType.
 155
 156   @param  [in]  DataNode   Pointer to a data node.
 157   @param  [in]  DataType   DataType to check.
 158
 159   @retval TRUE    The node is a data node and
 160                   the DataType match.
 161   @retval FALSE   Otherwise.
 162 **/
 163 BOOLEAN
 164 EFIAPI
 165 AmlNodeHasDataType (
 166   IN  AML_DATA_NODE_HANDLE    DataNode,
 167   IN  EAML_NODE_DATA_TYPE     DataType
 168   )
 169 {
 170   EFI_STATUS            Status;
 171   EAML_NODE_DATA_TYPE   NodeDataType;
 172
 173   // Get the data type.
 174   Status = AmlGetNodeDataType (DataNode, &NodeDataType);
 175   if (EFI_ERROR (Status)) {
 176     ASSERT (0);
 177     return FALSE;
 178   }
 179
 180   // Check the data type.
 181   if (NodeDataType != DataType) {
 182     return FALSE;
 183   }
 184
 185   return TRUE;
 186 }
 187
 188 /** Check whether RdNode has the input RdDataType.
 189
 190   @param  [in]  RdNode      Pointer to a data node.
 191   @param  [in]  RdDataType  DataType to check.
 192
 193   @retval TRUE    The node is a Resource Data node and
 194                   the RdDataType match.
 195   @retval FALSE   Otherwise.
 196 **/
 197 BOOLEAN
 198 EFIAPI
 199 AmlNodeHasRdDataType (
 200   IN  AML_DATA_NODE_HANDLE    RdNode,
 201   IN  AML_RD_HEADER           RdDataType
 202   )
 203 {
 204   EFI_STATUS      Status;
 205   AML_RD_HEADER   NodeRdDataType;
 206
 207   // Get the resource data type.
 208   Status = AmlGetResourceDataType (
 209              RdNode,
 210              &NodeRdDataType
 211              );
 212   if (EFI_ERROR (Status)) {
 213     ASSERT (0);
 214     return FALSE;
 215   }
 216
 217   // Check the RdDataType.
 218   return AmlRdCompareDescId (&NodeRdDataType, RdDataType);
 219 }