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   {
  64     ASSERT (0);
  65     return FALSE;
  66   }
  67
  68   // Get the NameOp name, being in a data node
  69   // which is the first fixed argument (i.e. index 0).
  70   NameDataNode = (AML_DATA_NODE_HANDLE)AmlGetFixedArgument (
  71                                          NameOpNode,
  72                                          EAmlParseIndexTerm0
  73                                          );
  74   if ((NameDataNode == NULL)                                            ||
  75       (AmlGetNodeType ((AML_NODE_HANDLE)NameDataNode) != EAmlNodeData)  ||
  76       (!AmlNodeHasDataType (NameDataNode, EAmlNodeDataTypeNameString)))
  77   {
  78     ASSERT (0);
  79     return FALSE;
  80   }
  81
  82   // Get the size of the name.
  83   Status = AmlGetDataNodeBuffer (NameDataNode, NULL, &AmlNameSize);
  84   if (EFI_ERROR (Status)) {
  85     ASSERT (0);
  86     return FALSE;
  87   }
  88
  89   // Allocate memory to fetch the name.
  90   AmlName = AllocateZeroPool (AmlNameSize);
  91   if (AmlName == NULL) {
  92     ASSERT (0);
  93     return FALSE;
  94   }
  95
  96   // Fetch the name.
  97   Status = AmlGetDataNodeBuffer (NameDataNode, (UINT8 *)AmlName, &AmlNameSize);
  98   if (EFI_ERROR (Status)) {
  99     FreePool (AmlName);
 100     ASSERT (0);
 101     return FALSE;
 102   }
 103
 104   // Compare the input AslName and the AmlName stored in the NameOp node.
 105   RetVal = CompareAmlWithAslNameString (AmlName, AslName);
 106
 107   // Free the string buffer.
 108   FreePool (AmlName);
 109   return RetVal;
 110 }
 111
 112 /** Check whether ObjectNode has the input OpCode/SubOpcode couple.
 113
 114   @param  [in]  ObjectNode  Pointer to an object node.
 115   @param  [in]  OpCode      OpCode to check
 116   @param  [in]  SubOpCode   SubOpCode to check
 117
 118   @retval TRUE    The node is an object node and
 119                   the Opcode and SubOpCode match.
 120   @retval FALSE   Otherwise.
 121 **/
 122 BOOLEAN
 123 EFIAPI
 124 AmlNodeHasOpCode (
 125   IN  AML_OBJECT_NODE_HANDLE  ObjectNode,
 126   IN  UINT8                   OpCode,
 127   IN  UINT8                   SubOpCode
 128   )
 129 {
 130   EFI_STATUS  Status;
 131   UINT8       NodeOpCode;
 132   UINT8       NodeSubOpCode;
 133
 134   // Get the Node information.
 135   Status = AmlGetObjectNodeInfo (
 136              ObjectNode,
 137              &NodeOpCode,
 138              &NodeSubOpCode,
 139              NULL,
 140              NULL
 141              );
 142   if (EFI_ERROR (Status)) {
 143     ASSERT (0);
 144     return FALSE;
 145   }
 146
 147   // Check the OpCode and SubOpCode.
 148   if ((OpCode != NodeOpCode)  ||
 149       (SubOpCode != NodeSubOpCode))
 150   {
 151     return FALSE;
 152   }
 153
 154   return TRUE;
 155 }
 156
 157 /** Check whether DataNode has the input DataType.
 158
 159   @param  [in]  DataNode   Pointer to a data node.
 160   @param  [in]  DataType   DataType to check.
 161
 162   @retval TRUE    The node is a data node and
 163                   the DataType match.
 164   @retval FALSE   Otherwise.
 165 **/
 166 BOOLEAN
 167 EFIAPI
 168 AmlNodeHasDataType (
 169   IN  AML_DATA_NODE_HANDLE  DataNode,
 170   IN  EAML_NODE_DATA_TYPE   DataType
 171   )
 172 {
 173   EFI_STATUS           Status;
 174   EAML_NODE_DATA_TYPE  NodeDataType;
 175
 176   // Get the data type.
 177   Status = AmlGetNodeDataType (DataNode, &NodeDataType);
 178   if (EFI_ERROR (Status)) {
 179     ASSERT (0);
 180     return FALSE;
 181   }
 182
 183   // Check the data type.
 184   if (NodeDataType != DataType) {
 185     return FALSE;
 186   }
 187
 188   return TRUE;
 189 }
 190
 191 /** Check whether RdNode has the input RdDataType.
 192
 193   @param  [in]  RdNode      Pointer to a data node.
 194   @param  [in]  RdDataType  DataType to check.
 195
 196   @retval TRUE    The node is a Resource Data node and
 197                   the RdDataType match.
 198   @retval FALSE   Otherwise.
 199 **/
 200 BOOLEAN
 201 EFIAPI
 202 AmlNodeHasRdDataType (
 203   IN  AML_DATA_NODE_HANDLE  RdNode,
 204   IN  AML_RD_HEADER         RdDataType
 205   )
 206 {
 207   EFI_STATUS     Status;
 208   AML_RD_HEADER  NodeRdDataType;
 209
 210   // Get the resource data type.
 211   Status = AmlGetResourceDataType (
 212              RdNode,
 213              &NodeRdDataType
 214              );
 215   if (EFI_ERROR (Status)) {
 216     ASSERT (0);
 217     return FALSE;
 218   }
 219
 220   // Check the RdDataType.
 221   return AmlRdCompareDescId (&NodeRdDataType, RdDataType);
 222 }