path: root/MdeModulePkg/Universal/Acpi/AcpiTableDxe/AmlNamespace.c

/** @file
  ACPI Sdt Protocol Driver

  Copyright (c) 2010, Intel Corporation. All rights reserved. <BR>
  This program and the accompanying materials
  are licensed and made available under the terms and conditions of the BSD License
  which accompanies this distribution.  The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.php

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#include "AcpiTable.h"

/**
  Construct node list according to the AML handle.
  
  @param[in]    AmlHandle            AML handle.
  @param[in]    AmlRootNodeList      AML root node list.
  @param[in]    AmlParentNodeList    AML parent node list.
  
  @retval       EFI_SUCCESS           Success.
  @retval       EFI_INVALID_PARAMETER AML handle does not refer to a valid ACPI object.
**/
EFI_STATUS
AmlConstructNodeList (
  IN EFI_AML_HANDLE      *AmlHandle,
  IN EFI_AML_NODE_LIST   *AmlRootNodeList,
  IN EFI_AML_NODE_LIST   *AmlParentNodeList
  );

/**
  Create AML Node.
  
  @param[in]    NameSeg              AML NameSeg.
  @param[in]    Parent               AML parent node list.
  @param[in]    AmlByteEncoding      AML Byte Encoding.
  
  @return       AML Node.
**/
EFI_AML_NODE_LIST *
AmlCreateNode (
  IN UINT8              *NameSeg,
  IN EFI_AML_NODE_LIST  *Parent,
  IN AML_BYTE_ENCODING  *AmlByteEncoding
  )
{
  EFI_AML_NODE_LIST      *AmlNodeList;

  AmlNodeList = AllocatePool (sizeof(*AmlNodeList));
  ASSERT (AmlNodeList != NULL);

  AmlNodeList->Signature = EFI_AML_NODE_LIST_SIGNATURE;
  CopyMem (AmlNodeList->Name, NameSeg, AML_NAME_SEG_SIZE);
  AmlNodeList->Buffer    = NULL;
  AmlNodeList->Size      = 0;
  InitializeListHead (&AmlNodeList->Link);
  InitializeListHead (&AmlNodeList->Children);
  AmlNodeList->Parent = Parent;
  AmlNodeList->AmlByteEncoding = AmlByteEncoding;

  return AmlNodeList;
}

/**
  Find the AML NameSeg in the children of AmlParentNodeList.
  
  @param[in]    NameSeg              AML NameSeg.
  @param[in]    AmlParentNodeList    AML parent node list.
  @param[in]    Create               TRUE means to create node if not found.
  
  @return       AmlChildNode whoes name is same as NameSeg.
**/
EFI_AML_NODE_LIST *
AmlFindNodeInThis (
  IN UINT8               *NameSeg,
  IN EFI_AML_NODE_LIST   *AmlParentNodeList,
  IN BOOLEAN             Create
  )
{
  EFI_AML_NODE_LIST      *CurrentAmlNodeList;
  LIST_ENTRY             *CurrentLink;
  LIST_ENTRY             *StartLink;
  EFI_AML_NODE_LIST      *AmlNodeList;

  StartLink   = &AmlParentNodeList->Children;
  CurrentLink = StartLink->ForwardLink;

  while (CurrentLink != StartLink) {
    CurrentAmlNodeList = EFI_AML_NODE_LIST_FROM_LINK (CurrentLink);
    //
    // AML name is same as the one stored
    //
    if (CompareMem (CurrentAmlNodeList->Name, NameSeg, AML_NAME_SEG_SIZE) == 0) {
      //
      // Good! Found it
      //
      return CurrentAmlNodeList;
    }
    CurrentLink = CurrentLink->ForwardLink;
  }

  //
  // Not found
  //
  if (!Create) {
    return NULL;
  }

  //
  // Create new node with NULL buffer - it means namespace not be returned.
  //
  AmlNodeList = AmlCreateNode (NameSeg, AmlParentNodeList, NULL);
  InsertTailList (&AmlParentNodeList->Children, &AmlNodeList->Link);

  return AmlNodeList;
}

/**
  Find the AML NameString in the children of AmlParentNodeList or AmlRootNodeList.
  
  @param[in]    NameString           AML NameString.
  @param[in]    AmlRootNodeList      AML root node list.
  @param[in]    AmlParentNodeList    AML parent node list.
  @param[in]    Create               TRUE means to create node if not found.
  
  @return       AmlChildNode whoes name is same as NameSeg.
**/
EFI_AML_NODE_LIST *
AmlFindNodeInTheTree (
  IN UINT8               *NameString,
  IN EFI_AML_NODE_LIST   *AmlRootNodeList,
  IN EFI_AML_NODE_LIST   *AmlParentNodeList,
  IN BOOLEAN             Create
  )
{
  UINT8               *Buffer;
  EFI_AML_NODE_LIST   *AmlNodeList;
  EFI_AML_NODE_LIST   *AmlCurrentNodeList;
  UINT8               Index;
  UINT8               SegCount;

  Buffer = NameString;

  //
  // Handle root or parent prefix
  //
  if (*Buffer == AML_ROOT_CHAR) {
    AmlCurrentNodeList = AmlRootNodeList;
    Buffer += 1;
  } else if (*Buffer == AML_PARENT_PREFIX_CHAR) {
    AmlCurrentNodeList = AmlParentNodeList;
    do {
      if (AmlCurrentNodeList->Parent != NULL) {
        AmlCurrentNodeList = AmlCurrentNodeList->Parent;
      } else {
        //
        // Only root has no parent
        //
        ASSERT (AmlCurrentNodeList == AmlRootNodeList);
      }
      Buffer += 1;
    } while (*Buffer == AML_PARENT_PREFIX_CHAR);
  } else {
    AmlCurrentNodeList = AmlParentNodeList;
  }
  
  //
  // Handle name segment
  //
  if (*Buffer == AML_DUAL_NAME_PREFIX) {
    Buffer += 1;
    SegCount = 2;
  } else if (*Buffer == AML_MULTI_NAME_PREFIX) {
    Buffer += 1;
    SegCount = *Buffer;
    Buffer += 1;
  } else if (*Buffer == 0) {
    //
    // NULL name, only for Root
    //
    ASSERT (AmlCurrentNodeList == AmlRootNodeList);
    return AmlCurrentNodeList;
  } else {
    SegCount = 1;
  }

  //
  // Handle NamePath
  //
  Index = 0;
  do {
    AmlNodeList = AmlFindNodeInThis (Buffer, AmlCurrentNodeList, Create);
    if (AmlNodeList == NULL) {
      return NULL;
    }
    AmlCurrentNodeList = AmlNodeList;
    Buffer += AML_NAME_SEG_SIZE;
    Index ++;
  } while (Index < SegCount);

  return AmlNodeList;
}

/**
  Insert the NameString to the AmlNodeList.
  
  @param[in]    NameString           AML NameString.
  @param[in]    Buffer               Buffer for the Node.
  @param[in]    Size                 Size for the Node.
  @param[in]    AmlRootNodeList      AML root node list.
  @param[in]    AmlParentNodeList    AML parent node list.
  
  @return       AmlChildNode whoes name is NameString.
**/
EFI_AML_NODE_LIST *
AmlInsertNodeToTree (
  IN UINT8               *NameString,
  IN VOID                *Buffer,
  IN UINTN               Size,
  IN EFI_AML_NODE_LIST   *AmlRootNodeList,
  IN EFI_AML_NODE_LIST   *AmlParentNodeList
  )
{
  EFI_AML_NODE_LIST   *AmlNodeList;

  AmlNodeList = AmlFindNodeInTheTree (
                  NameString,
                  AmlRootNodeList,
                  AmlParentNodeList,
                  TRUE  // Find and Create
                  );
  ASSERT (AmlNodeList != NULL);
  if (AmlNodeList == NULL) {
    return NULL;
  }

  //
  // Check buffer
  //
  if (AmlNodeList->Buffer == NULL) {
    //
    // NULL means new added one or SCOPE_OP
    //
    if (*(UINT8 *)Buffer != AML_SCOPE_OP) {
      //
      // We need check if new one is SCOPE_OP, because SCOPE_OP just means namespace, not a real device.
      // We should not return SCOPE_OP.
      //
      AmlNodeList->Buffer = Buffer;
      AmlNodeList->Size   = Size;
      AmlNodeList->AmlByteEncoding = AmlSearchByOpByte (Buffer);
    }
    return AmlNodeList;
  }

  //
  // Already added
  //
  if (*(UINT8 *)Buffer == AML_SCOPE_OP) {
    //
    // The new one is SCOPE_OP, OK just return;
    //
    return AmlNodeList;
  }

  //
  // Oops!!!, There must be something wrong.
  //
  DEBUG ((EFI_D_ERROR, "AML: Override Happen - %a!\n", NameString));
  DEBUG ((EFI_D_ERROR, "AML: Existing Node - %x\n", AmlNodeList->Buffer));
  DEBUG ((EFI_D_ERROR, "AML: New Buffer - %x\n", Buffer));

  return NULL;
}

/**
  Construct child node list according to the AML handle.
  
  @param[in]    AmlHandle            AML handle.
  @param[in]    AmlRootNodeList      AML root node list.
  @param[in]    AmlParentNodeList    AML parent node list.
  
  @retval       EFI_SUCCESS           Success.
  @retval       EFI_INVALID_PARAMETER AML handle does not refer to a valid ACPI object.
**/
EFI_STATUS
AmlConstructNodeListForChild (
  IN EFI_AML_HANDLE      *AmlHandle,
  IN EFI_AML_NODE_LIST   *AmlRootNodeList,
  IN EFI_AML_NODE_LIST   *AmlParentNodeList
  )
{
  AML_BYTE_ENCODING   *AmlByteEncoding;
  UINT8               *Buffer;
  UINTN               BufferSize;
  UINT8               *CurrentBuffer;
  EFI_AML_HANDLE      *AmlChildHandle;
  EFI_STATUS          Status;

  AmlByteEncoding = AmlHandle->AmlByteEncoding;
  Buffer          = AmlHandle->Buffer;
  BufferSize      = AmlHandle->Size;

  //
  // Check if we need recursively add node
  //
  if ((AmlByteEncoding->Attribute & AML_HAS_CHILD_OBJ) == 0) {
    //
    // No more node need to be added
    //
    return EFI_SUCCESS;
  }

  //
  // Do we need add node within METHOD?
  // Yes, just add Object is OK. But we need filter NameString for METHOD invoke.
  //

  //
  // Now, we get the last node.
  //
  Status = AmlGetOffsetAfterLastOption (AmlHandle, &CurrentBuffer);
  if (EFI_ERROR (Status)) {
    return EFI_INVALID_PARAMETER;
  }

  //
  // Go through all the reset buffer.
  //
  while ((UINTN)CurrentBuffer < (UINTN)Buffer + BufferSize) {
    //
    // Find the child node.
    //
    Status = SdtOpenEx (CurrentBuffer, (UINTN)Buffer + BufferSize - (UINTN)CurrentBuffer, (EFI_ACPI_HANDLE *)&AmlChildHandle);
    if (EFI_ERROR (Status)) {
      //
      // No child found, break now.
      //
      break;
    }

    //
    // Good, find the child. Construct node recursively
    //
    Status = AmlConstructNodeList (
               AmlChildHandle,
               AmlRootNodeList,
               AmlParentNodeList
               );
    if (EFI_ERROR (Status)) {
      break;
    }

    //
    // Parse next one
    //
    CurrentBuffer += AmlChildHandle->Size;

    Close ((EFI_ACPI_HANDLE)AmlChildHandle);
  }

  return EFI_SUCCESS;
}

/**
  Construct node list according to the AML handle.
  
  @param[in]    AmlHandle            AML handle.
  @param[in]    AmlRootNodeList      AML root node list.
  @param[in]    AmlParentNodeList    AML parent node list.
  
  @retval       EFI_SUCCESS           Success.
  @retval       EFI_INVALID_PARAMETER AML handle does not refer to a valid ACPI object.
**/
EFI_STATUS
AmlConstructNodeList (
  IN EFI_AML_HANDLE      *AmlHandle,
  IN EFI_AML_NODE_LIST   *AmlRootNodeList,
  IN EFI_AML_NODE_LIST   *AmlParentNodeList
  )
{
  VOID                *NameString;
  EFI_AML_NODE_LIST   *AmlNodeList;

  //
  // 1. Check if there is need to construct node for this OpCode.
  //
  if ((AmlHandle->AmlByteEncoding->Attribute & AML_IN_NAMESPACE) == 0) {
    //
    // No need to construct node, so we just skip this OpCode.
    //
    return EFI_SUCCESS;
  }

  //
  // 2. Now, we need construct node for this OpCode.
  //
  NameString = AmlGetObjectName (AmlHandle);
  if (NameString == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  //
  // Now, we need to insert node to the node list.
  // NOTE: The name here could be AML NameString. So the callee need parse it.
  //
  AmlNodeList = AmlInsertNodeToTree (NameString, AmlHandle->Buffer, AmlHandle->Size, AmlRootNodeList, AmlParentNodeList);
  ASSERT (AmlNodeList != NULL);

  //
  // 3. Ok, we need to parse the object list to see if there are more node to be added.
  //
  return AmlConstructNodeListForChild (AmlHandle, AmlRootNodeList, AmlNodeList);
}

/**
  Destruct node list
  
  @param[in]    AmlParentNodeList    AML parent node list.
**/
VOID
AmlDestructNodeList (
  IN EFI_AML_NODE_LIST *AmlParentNodeList
  )
{
  EFI_AML_NODE_LIST      *CurrentAmlNodeList;
  LIST_ENTRY             *CurrentLink;
  LIST_ENTRY             *StartLink;

  //
  // Get the children link
  //
  StartLink   = &AmlParentNodeList->Children;
  CurrentLink = StartLink->ForwardLink;

  //
  // Go through all the children
  //
  while (CurrentLink != StartLink) {
    //
    // Destruct the child's list recursively
    //
    CurrentAmlNodeList = EFI_AML_NODE_LIST_FROM_LINK (CurrentLink);
    CurrentLink = CurrentLink->ForwardLink;

    //
    // Remove this child from list and free the node
    //
    RemoveEntryList (&(CurrentAmlNodeList->Link));

    AmlDestructNodeList (CurrentAmlNodeList);
  }

  //
  // Done.
  //
  FreePool (AmlParentNodeList);
  return ;
}

/**
  Dump node list
  
  @param[in]    AmlParentNodeList    AML parent node list.
  @param[in]    Level                Output debug level.
**/
VOID
AmlDumpNodeInfo (
  IN EFI_AML_NODE_LIST *AmlParentNodeList,
  IN UINTN             Level
  )
{
  EFI_AML_NODE_LIST      *CurrentAmlNodeList;
  volatile LIST_ENTRY    *CurrentLink;
  UINTN                  Index;

  CurrentLink = AmlParentNodeList->Children.ForwardLink;

  if (Level == 0) {
    DEBUG ((EFI_D_ERROR, "\\"));
  } else {
    for (Index = 0; Index < Level; Index++) {
      DEBUG ((EFI_D_ERROR, "    "));
    }
    AmlPrintNameSeg (AmlParentNodeList->Name);
  }
  DEBUG ((EFI_D_ERROR, "\n"));

  while (CurrentLink != &AmlParentNodeList->Children) {
    CurrentAmlNodeList = EFI_AML_NODE_LIST_FROM_LINK (CurrentLink);
    AmlDumpNodeInfo (CurrentAmlNodeList, Level + 1);
    CurrentLink = CurrentLink->ForwardLink;
  }

  return ;
}

/**
  Returns the handle of the ACPI object representing the specified ACPI AML path
  
  @param[in]    AmlHandle   Points to the handle of the object representing the starting point for the path search.
  @param[in]    AmlPath     Points to the ACPI AML path.
  @param[out]   Buffer      On return, points to the ACPI object which represents AcpiPath, relative to
                            HandleIn.
  @param[in]    FromRoot    TRUE means to find AML path from \ (Root) Node.
                            FALSE means to find AML path from this Node (The HandleIn).
                            
  @retval EFI_SUCCESS           Success
  @retval EFI_INVALID_PARAMETER HandleIn does not refer to a valid ACPI object.                            
**/
EFI_STATUS
AmlFindPath (
  IN    EFI_AML_HANDLE  *AmlHandle,
  IN    UINT8           *AmlPath,
  OUT   VOID            **Buffer,
  IN    BOOLEAN         FromRoot
  )
{
  EFI_AML_NODE_LIST   *AmlRootNodeList;
  EFI_STATUS          Status;
  EFI_AML_NODE_LIST   *AmlNodeList;
  UINT8               RootNameSeg[AML_NAME_SEG_SIZE];
  EFI_AML_NODE_LIST   *CurrentAmlNodeList;
  LIST_ENTRY          *CurrentLink;

  //
  // 1. create tree
  //

  //
  // Create root handle
  //
  RootNameSeg[0] = AML_ROOT_CHAR;
  RootNameSeg[1] = 0;
  AmlRootNodeList = AmlCreateNode (RootNameSeg, NULL, AmlHandle->AmlByteEncoding);

  Status = AmlConstructNodeList (
             AmlHandle,
             AmlRootNodeList, // Root
             AmlRootNodeList  // Parent
             );
  if (EFI_ERROR (Status)) {
    return EFI_INVALID_PARAMETER;
  }

  DEBUG_CODE_BEGIN ();
  DEBUG ((EFI_D_ERROR, "AcpiSdt: NameSpace:\n"));
  AmlDumpNodeInfo (AmlRootNodeList, 0);
  DEBUG_CODE_END ();

  //
  // 2. Search the node in the tree
  //
  if (FromRoot) {
    //
    // Search from Root
    //
    CurrentAmlNodeList = AmlRootNodeList;
  } else {
    //
    // Search from this node, NOT ROOT.
    // Since we insert node to ROOT one by one, we just get the first node and search from it.
    //
    CurrentLink = AmlRootNodeList->Children.ForwardLink;
    if (CurrentLink != &AmlRootNodeList->Children) {
      //
      // First node
      //
      CurrentAmlNodeList = EFI_AML_NODE_LIST_FROM_LINK (CurrentLink);
    } else {
      //
      // No child
      //
      CurrentAmlNodeList = NULL;
    }
  }

  //
  // Search
  //
  if (CurrentAmlNodeList != NULL) {
    DEBUG_CODE_BEGIN ();
    DEBUG ((EFI_D_ERROR, "AcpiSdt: Search from: \\"));
    AmlPrintNameSeg (CurrentAmlNodeList->Name);
    DEBUG ((EFI_D_ERROR, "\n"));
    DEBUG_CODE_END ();
    AmlNodeList = AmlFindNodeInTheTree (
                    AmlPath,
                    AmlRootNodeList,    // Root
                    CurrentAmlNodeList, // Parent
                    FALSE
                    );
  } else {
    AmlNodeList = NULL;
  }

  *Buffer = NULL;
  Status = EFI_SUCCESS;
  if (AmlNodeList != NULL && AmlNodeList->Buffer != NULL) {
    *Buffer = AmlNodeList->Buffer;
  }

  //
  // 3. free the tree
  //
  AmlDestructNodeList (AmlRootNodeList);

  return Status;
}