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authorPierre Gondois <pierre.gondois@arm.com>2020-08-05 11:26:01 +0100
committermergify[bot] <37929162+mergify[bot]@users.noreply.github.com>2020-08-13 18:00:06 +0000
commitbb4e93925333625cdcd97f6f174f79e7ed48afa7 (patch)
treef9f48a8f27f883d4012867914659951940fb98f9 /DynamicTablesPkg
parentfeea6514486f9dbf6a657e25dd32035d997560de (diff)
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DynamicTablesPkg: AML Method parser
The AML language allows a Definition Block to implement methods that an Operating System can invoke at runtime. Although Dynamic AML does not provide interfaces to modify AML methods; an AML template code may contain methods and/or method invocations. Method definitions have an opcode defined in the AML encoding and can be easily parsed. However, the language does not define an opcode for method invocation. Method invocations are represented as a NameString followed by the arguments to the method. This poses a significant challenge for the AML parser as it has to determine if a NameString appearing in the AML byte stream is a method invocation and if it is a method invocation, then how many arguments follow. This also means the Method definition must occur prior to the method invocation in the AML byte stream. This is a hard requirement for the AML parser. The AML method parser maintains a NameSpaceRefList that keeps a track of every namespace node and its raw AML absolute path. The AmlIsMethodInvocation() searches the NameSpaceRefList to determine if a NameString matches a Method definition. A pseudo opcode has been defined in the AML encoding to represent the Method invocation in the AML tree. The AML encoding for method invocations in the ACPI specification 6.3 is: MethodInvocation := NameString TermArgList The AmlLib library redefines this as: MethodInvocation := MethodInvocationOp NameString ArgumentCount TermArgList ArgumentCount := ByteData Where MethodInvocationOp is the pseudo opcode and ArgumentCount is the number of arguments passed to the method. NOTE: The AmlLib library's definition for a method invocation only applies to the representation of method invocation node in the AML tree. When computing the size of a tree or serialising it, the additional data is not taken into account i.e. the MethodInvocationOp and the ArgumentCount are stripped before serialising. Method invocation nodes have the AML_METHOD_INVOVATION attribute set in the AmlLib library's representation of the AML encoding. Signed-off-by: Pierre Gondois <pierre.gondois@arm.com> Signed-off-by: Sami Mujawar <sami.mujawar@arm.com> Reviewed-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
Diffstat (limited to 'DynamicTablesPkg')
-rw-r--r--DynamicTablesPkg/Library/Common/AmlLib/Parser/AmlMethodParser.c1458
-rw-r--r--DynamicTablesPkg/Library/Common/AmlLib/Parser/AmlMethodParser.h188
2 files changed, 1646 insertions, 0 deletions
diff --git a/DynamicTablesPkg/Library/Common/AmlLib/Parser/AmlMethodParser.c b/DynamicTablesPkg/Library/Common/AmlLib/Parser/AmlMethodParser.c
new file mode 100644
index 0000000000..bc98d950b5
--- /dev/null
+++ b/DynamicTablesPkg/Library/Common/AmlLib/Parser/AmlMethodParser.c
@@ -0,0 +1,1458 @@
+/** @file
+ AML Method Parser.
+
+ Copyright (c) 2020, Arm Limited. All rights reserved.<BR>
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#include <Parser/AmlMethodParser.h>
+
+#include <AmlCoreInterface.h>
+#include <AmlDbgPrint/AmlDbgPrint.h>
+#include <NameSpace/AmlNameSpace.h>
+#include <Parser/AmlParser.h>
+#include <Tree/AmlNode.h>
+#include <Tree/AmlTree.h>
+#include <String/AmlString.h>
+
+/** Delete a namespace reference node and its pathname.
+
+ It is the caller's responsibility to check the NameSpaceRefNode has been
+ removed from any list the node is part of.
+
+ @param [in] NameSpaceRefNode Pointer to an AML_NAMESPACE_REF_NODE.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+**/
+STATIC
+EFI_STATUS
+EFIAPI
+AmlDeleteNameSpaceRefNode (
+ IN AML_NAMESPACE_REF_NODE * NameSpaceRefNode
+ )
+{
+ if (NameSpaceRefNode == NULL) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ if (NameSpaceRefNode->RawAbsolutePath != NULL) {
+ FreePool ((CHAR8*)NameSpaceRefNode->RawAbsolutePath);
+ } else {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ FreePool (NameSpaceRefNode);
+ return EFI_SUCCESS;
+}
+
+/** Delete a list of namespace reference nodes.
+
+ @param [in] NameSpaceRefList List of namespace reference nodes.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+**/
+EFI_STATUS
+EFIAPI
+AmlDeleteNameSpaceRefList (
+ IN LIST_ENTRY * NameSpaceRefList
+ )
+{
+ EFI_STATUS Status;
+ LIST_ENTRY * CurrentLink;
+
+ if (NameSpaceRefList == NULL) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ while (!IsListEmpty (NameSpaceRefList)) {
+ CurrentLink = NameSpaceRefList->ForwardLink;
+ RemoveEntryList (CurrentLink);
+ Status = AmlDeleteNameSpaceRefNode (
+ (AML_NAMESPACE_REF_NODE*)CurrentLink
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+ } // while
+
+ return EFI_SUCCESS;
+}
+
+/** Create an AML_NAMESPACE_REF_NODE.
+
+ A Buffer is allocated to store the raw AML absolute path.
+
+ @param [in] ObjectNode Node being part of the namespace.
+ Must be have the AML_IN_NAMESPACE
+ attribute.
+ @param [in] RawAbsolutePath AML raw absolute path of the ObjectNode.
+ A raw NameString is a concatenated list
+ of 4 chars long names.
+ @param [in] RawAbsolutePathSize Size of the RawAbsolutePath buffer.
+ @param [out] NameSpaceRefNodePtr The created AML_METHOD_REF_NODE.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+ @retval EFI_OUT_OF_RESOURCES Could not allocate memory.
+**/
+STATIC
+EFI_STATUS
+EFIAPI
+AmlCreateMethodRefNode (
+ IN CONST AML_OBJECT_NODE * ObjectNode,
+ IN CONST CHAR8 * RawAbsolutePath,
+ IN UINT32 RawAbsolutePathSize,
+ OUT AML_NAMESPACE_REF_NODE ** NameSpaceRefNodePtr
+ )
+{
+ AML_NAMESPACE_REF_NODE * NameSpaceRefNode;
+
+ if (!AmlNodeHasAttribute (ObjectNode, AML_IN_NAMESPACE) ||
+ (RawAbsolutePath == NULL) ||
+ (RawAbsolutePathSize == 0) ||
+ (NameSpaceRefNodePtr == NULL)) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ NameSpaceRefNode = AllocateZeroPool (sizeof (AML_NAMESPACE_REF_NODE));
+ if (NameSpaceRefNode == NULL) {
+ ASSERT (0);
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ NameSpaceRefNode->RawAbsolutePathSize = RawAbsolutePathSize;
+ NameSpaceRefNode->RawAbsolutePath = AllocateCopyPool (
+ RawAbsolutePathSize,
+ RawAbsolutePath
+ );
+ if (NameSpaceRefNode->RawAbsolutePath == NULL) {
+ FreePool (NameSpaceRefNode);
+ ASSERT (0);
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ InitializeListHead (&NameSpaceRefNode->Link);
+
+ NameSpaceRefNode->NodeRef = ObjectNode;
+ *NameSpaceRefNodePtr = NameSpaceRefNode;
+
+ return EFI_SUCCESS;
+}
+
+#if !defined (MDEPKG_NDEBUG)
+
+/** Print the list of raw absolute paths of the NameSpace reference list.
+
+ @param [in] NameSpaceRefList List of NameSpace reference nodes.
+**/
+VOID
+EFIAPI
+AmlDbgPrintNameSpaceRefList (
+ IN CONST LIST_ENTRY * NameSpaceRefList
+ )
+{
+ LIST_ENTRY * CurrLink;
+ AML_NAMESPACE_REF_NODE * CurrNameSpaceNode;
+
+ if (NameSpaceRefList == NULL) {
+ ASSERT (0);
+ return;
+ }
+
+ DEBUG ((DEBUG_INFO, "AmlMethodParser: List of available raw AML paths:\n"));
+
+ CurrLink = NameSpaceRefList->ForwardLink;
+ while (CurrLink != NameSpaceRefList) {
+ CurrNameSpaceNode = (AML_NAMESPACE_REF_NODE*)CurrLink;
+
+ AmlDbgPrintChars (
+ DEBUG_INFO,
+ CurrNameSpaceNode->RawAbsolutePath,
+ CurrNameSpaceNode->RawAbsolutePathSize
+ );
+ DEBUG ((DEBUG_INFO, "\n"));
+
+ CurrLink = CurrLink->ForwardLink;
+ }
+
+ DEBUG ((DEBUG_INFO, "\n"));
+}
+
+#endif // MDEPKG_NDEBUG
+
+/** From a forward stream pointing to a NameString,
+ initialize a raw backward stream.
+
+ StartOfStream
+ Fstream: CurrPos EndOfStream
+ v v
+ +-----------------------------------------+
+ |^^^[Multi-name prefix]AAAA.BBBB.CCCC |
+ +-----------------------------------------+
+ ^ ^
+ RawPathNameBStream: EndOfStream CurrPos
+ StartOfStream
+
+ No memory is allocated when initializing the stream.
+
+ @param [in] FStream Forward stream pointing to a NameString.
+ The stream must not be at its end.
+ @param [out] RawPathNameBStream Backward stream containing the
+ raw AML path.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+**/
+STATIC
+EFI_STATUS
+EFIAPI
+AmlInitRawPathBStream (
+ IN CONST AML_STREAM * FStream,
+ OUT AML_STREAM * RawPathNameBStream
+ )
+{
+ EFI_STATUS Status;
+
+ UINT8 * RawPathBuffer;
+ CONST CHAR8 * Buffer;
+
+ UINT32 Root;
+ UINT32 ParentPrefix;
+ UINT32 SegCount;
+
+ if (!IS_STREAM (FStream) ||
+ IS_END_OF_STREAM (FStream) ||
+ !IS_STREAM_FORWARD (FStream) ||
+ (RawPathNameBStream == NULL)) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ Buffer = (CONST CHAR8*)AmlStreamGetCurrPos (FStream);
+ if (Buffer == NULL) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ // Parse the NameString information.
+ Status = AmlParseNameStringInfo (
+ Buffer,
+ &Root,
+ &ParentPrefix,
+ &SegCount
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+
+ // Get the beginning of the raw NameString.
+ RawPathBuffer = (UINT8*)AmlGetFirstNameSeg (
+ Buffer,
+ Root,
+ ParentPrefix
+ );
+ if (RawPathBuffer == NULL) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ // Initialize a backward stream containing the raw path.
+ Status = AmlStreamInit (
+ RawPathNameBStream,
+ RawPathBuffer,
+ (SegCount * AML_NAME_SEG_SIZE),
+ EAmlStreamDirectionBackward
+ );
+ ASSERT_EFI_ERROR (Status);
+
+ return Status;
+}
+
+/** Get the first node in the ParentNode branch that is part of the
+ AML namespace and has its name defined.
+
+ This is different from getting the first namespace node. This function is
+ necessary because an absolute path is built while the tree is not complete
+ yet. The parsing is ongoing.
+
+ For instance, the ASL statement "CreateXXXField ()" adds a field in the
+ AML namespace, but the name it defines is the last fixed argument of the
+ corresponding object.
+ If an AML path is referenced in its first fixed argument, it is not
+ possible to resolve the name of the CreateXXXField object. However, the AML
+ path is not part of the scope created by the CreateXXXField object, so this
+ scope can be skipped.
+
+ In the following ASL code, the method invocation to MET0 is done in the
+ "CreateField" statement. The "CreateField" statement defines the "FIEL"
+ path in the AML namespace. However, MET0 must be not be resolved in the
+ "CreateField" object scope. It needs to be resolved in its parent.
+ ASL code:
+ Method (MET0, 0,,, BuffObj) {
+ Return (Buffer (0x1000) {})
+ }
+ CreateField (MET0(), 0x100, 0x4, FIEL)
+
+ @param [in] Node Node to get the first named node from, in
+ its hierarchy.
+ @param [out] OutNamedNode First named node in Node's hierarchy.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+**/
+STATIC
+EFI_STATUS
+EFIAPI
+AmlGetFirstNamedAncestorNode (
+ IN CONST AML_NODE_HEADER * Node,
+ OUT AML_NODE_HEADER ** OutNamedNode
+ )
+{
+ EFI_STATUS Status;
+ CONST AML_NODE_HEADER * NameSpaceNode;
+
+ if ((!IS_AML_OBJECT_NODE (Node) &&
+ !IS_AML_ROOT_NODE (Node)) ||
+ (OutNamedNode == NULL)) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ // If Node is not the root node and doesn't have a name defined yet,
+ // get the ancestor NameSpace node.
+ while (!IS_AML_ROOT_NODE (Node) &&
+ !(AmlNodeHasAttribute (
+ (CONST AML_OBJECT_NODE*)Node,
+ AML_IN_NAMESPACE) &&
+ AmlNodeGetName ((CONST AML_OBJECT_NODE*)Node) != NULL)) {
+ Status = AmlGetFirstAncestorNameSpaceNode (
+ Node,
+ (AML_NODE_HEADER**)&NameSpaceNode
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+ // The NameSpaceNode may not have its name defined as yet. In this
+ // case get the next ancestor node.
+ Node = NameSpaceNode;
+ }
+
+ *OutNamedNode = (AML_NODE_HEADER*)Node;
+
+ return EFI_SUCCESS;
+}
+
+/** From a ParentNode and a forward stream pointing to a relative path,
+ build a raw AML absolute path and return it in a backward stream.
+
+ No memory is allocated in this function, the out stream must be initialized
+ with a buffer long enough to hold any raw absolute AML path.
+
+ @param [in] ParentNode Parent node of the namespace
+ node from which the absolute
+ path is built. ParentNode isn't
+ necessarily a namespace node.
+ Must be a root or an object node.
+ @param [in] PathnameFStream Forward stream pointing to the
+ beginning of a pathname (any
+ NameString).
+ The stream must not be at its end.
+ @param [in, out] AbsolutePathBStream Backward stream where the raw
+ absolute path is written. The
+ stream must be already initialized.
+ The stream must not be at its end.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_BUFFER_TOO_SMALL No space left in the buffer.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+**/
+STATIC
+EFI_STATUS
+EFIAPI
+AmlBuildRawMethodAbsolutePath (
+ IN CONST AML_NODE_HEADER * ParentNode,
+ IN CONST AML_STREAM * PathnameFStream,
+ IN OUT AML_STREAM * AbsolutePathBStream
+ )
+{
+ EFI_STATUS Status;
+
+ AML_NODE_HEADER * NamedParentNode;
+ UINT8 * RawPathBuffer;
+ CONST CHAR8 * CurrPos;
+
+ UINT32 Root;
+ UINT32 ParentPrefix;
+ UINT32 SegCount;
+
+ if ((!IS_AML_OBJECT_NODE (ParentNode) &&
+ !IS_AML_ROOT_NODE (ParentNode)) ||
+ !IS_STREAM (PathnameFStream) ||
+ IS_END_OF_STREAM (PathnameFStream) ||
+ !IS_STREAM_FORWARD (PathnameFStream) ||
+ !IS_STREAM (AbsolutePathBStream) ||
+ IS_END_OF_STREAM (AbsolutePathBStream) ||
+ !IS_STREAM_BACKWARD (AbsolutePathBStream)) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ CurrPos = (CONST CHAR8*)AmlStreamGetCurrPos (PathnameFStream);
+ if (CurrPos == NULL) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ // Parse the NameString information.
+ Status = AmlParseNameStringInfo (
+ CurrPos,
+ &Root,
+ &ParentPrefix,
+ &SegCount
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+
+ // Copy the method invocation raw relative path at the end of the Stream.
+ if (SegCount != 0) {
+ // Get the beginning of the raw NameString.
+ RawPathBuffer = (UINT8*)AmlGetFirstNameSeg (
+ CurrPos,
+ Root,
+ ParentPrefix
+ );
+
+ Status = AmlStreamWrite (
+ AbsolutePathBStream,
+ RawPathBuffer,
+ SegCount * AML_NAME_SEG_SIZE
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+ }
+
+ // If the pathname contained an absolute path, this is finished, return.
+ if (Root) {
+ return Status;
+ }
+
+ // Get the first named node of the parent node in its hierarchy.
+ Status = AmlGetFirstNamedAncestorNode (ParentNode, &NamedParentNode);
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+
+ // Build the raw absolute path of the namespace node.
+ Status = AmlGetRawNameSpacePath (
+ NamedParentNode,
+ ParentPrefix,
+ AbsolutePathBStream
+ );
+ ASSERT_EFI_ERROR (Status);
+
+ return Status;
+}
+
+/** Compare two raw NameStrings stored in forward streams.
+ Compare them NameSeg by NameSeg (a NameSeg is 4 bytes long).
+
+ The two raw NameStrings can be of different size.
+
+ @param [in] RawFStream1 First forward stream to compare.
+ Points to the beginning of the raw NameString.
+ @param [in] RawFStream2 Second forward stream to compare.
+ Points to the beginning of the raw NameString.
+ @param [out] CompareCount Count of identic bytes.
+ Must be a multiple of 4 (size of a NameSeg).
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+**/
+STATIC
+EFI_STATUS
+EFIAPI
+AmlCompareRawNameString (
+ IN CONST AML_STREAM * RawFStream1,
+ IN CONST AML_STREAM * RawFStream2,
+ OUT UINT32 * CompareCount
+ )
+{
+ EFI_STATUS Status;
+ UINT32 Index;
+
+ AML_STREAM RawFStream1Clone;
+ AML_STREAM RawFStream2Clone;
+ UINT32 Stream1Size;
+ UINT32 Stream2Size;
+ UINT32 CompareLen;
+
+ // Raw NameStrings have a size that is a multiple of the size of NameSegs.
+ if (!IS_STREAM (RawFStream1) ||
+ IS_END_OF_STREAM (RawFStream1) ||
+ !IS_STREAM_FORWARD (RawFStream1) ||
+ !IS_STREAM (RawFStream2) ||
+ IS_END_OF_STREAM (RawFStream2) ||
+ (CompareCount == NULL)) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ Stream1Size = AmlStreamGetFreeSpace (RawFStream1);
+ if ((Stream1Size & (AML_NAME_SEG_SIZE - 1)) != 0) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ Stream2Size = AmlStreamGetFreeSpace (RawFStream2);
+ if ((Stream2Size & (AML_NAME_SEG_SIZE - 1)) != 0) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ Status = AmlStreamClone (RawFStream1, &RawFStream1Clone);
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+
+ Status = AmlStreamClone (RawFStream2, &RawFStream2Clone);
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+
+ CompareLen = MIN (Stream1Size, Stream2Size);
+ Index = 0;
+ // Check there is enough space for a NameSeg in both Stream1 and Stream2.
+ while (Index < CompareLen) {
+ if (!AmlStreamCmp (
+ &RawFStream1Clone,
+ &RawFStream2Clone,
+ AML_NAME_SEG_SIZE)
+ ) {
+ // NameSegs are different. Break.
+ break;
+ }
+
+ Status = AmlStreamProgress (&RawFStream1Clone, AML_NAME_SEG_SIZE);
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+ Status = AmlStreamProgress (&RawFStream2Clone, AML_NAME_SEG_SIZE);
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+
+ Index += AML_NAME_SEG_SIZE;
+ }
+
+ *CompareCount = Index;
+
+ return EFI_SUCCESS;
+}
+
+/** Check whether an alias can be resolved to a method definition.
+
+ Indeed, the following ASL code must be handled:
+ Method (MET0, 1) {
+ Return (0x9)
+ }
+ Alias (\MET0, \ALI0)
+ Alias (\ALI0, \ALI1)
+ \ALI1(0x5)
+ When searching for \ALI1 in the AML NameSpace, it resolves to \ALI0.
+ When searching for \ALI0 in the AML NameSpace, it resolves to \MET0.
+ When searching for \MET0 in the AML NameSpace, it resolves to a method
+ definition.
+
+ This method is a wrapper to recursively call AmlFindMethodDefinition.
+
+ @param [in] AliasNode Pointer to an Alias object node.
+ @param [in] NameSpaceRefList List of NameSpaceRef nodes.
+ @param [out] OutNameSpaceRefNode If success, and if the alias is resolved
+ to a method definition (this can go
+ through other alias indirections),
+ containing the corresponding
+ NameSpaceRef node.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+**/
+STATIC
+EFI_STATUS
+EFIAPI
+AmlResolveAliasMethod (
+ IN CONST AML_OBJECT_NODE * AliasNode,
+ IN CONST LIST_ENTRY * NameSpaceRefList,
+ OUT AML_NAMESPACE_REF_NODE ** OutNameSpaceRefNode
+ )
+{
+ EFI_STATUS Status;
+ AML_STREAM SourceAliasFStream;
+ CONST AML_DATA_NODE * DataNode;
+
+ if (!AmlNodeCompareOpCode (AliasNode, AML_ALIAS_OP, 0) ||
+ (NameSpaceRefList == NULL) ||
+ (OutNameSpaceRefNode == NULL)) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ // The aliased NameString (the source name) is the first fixed argument,
+ // cf. ACPI6.3 spec, s19.6.4: Alias (SourceObject, AliasObject)
+ DataNode = (CONST AML_DATA_NODE*)AmlGetFixedArgument (
+ (AML_OBJECT_NODE*)AliasNode,
+ EAmlParseIndexTerm0
+ );
+ if (DataNode == NULL) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ // Initialize a stream on the source alias NameString.
+ Status = AmlStreamInit (
+ &SourceAliasFStream,
+ DataNode->Buffer,
+ DataNode->Size,
+ EAmlStreamDirectionForward
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+
+ // Recursively check whether the source alias NameString
+ // is a method invocation.
+ Status = AmlIsMethodInvocation (
+ AmlGetParent ((AML_NODE_HEADER*)AliasNode),
+ &SourceAliasFStream,
+ NameSpaceRefList,
+ OutNameSpaceRefNode
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ }
+
+ return Status;
+}
+
+/** Iterate through the MethodList to find the best namespace resolution.
+ If the pathname resolves to a method definition, returns it.
+
+ For instance, if the AML namespace is:
+ \
+ \-MET0 <- Device definition, absolute path: \MET0
+ \-AAAA
+ \-MET0 <- Method definition, absolute path: \AAAA.MET0
+ \-MET1 <- Method definition, absolute path: \AAAA.MET1
+ \-BBBB
+ \-CCCC
+ \-DDDD
+ \-MET0 <- Method definition, absolute path: \AAAA.BBBB.CCCC.DDDD.MET0
+
+ The list of the available pathnames is:
+ [NameSpaceRefList]
+ - \MET0 <- Device definition
+ - \AAAA
+ - \AAAA.MET0 <- Method definition
+ - \AAAA.MET1 <- Method definition
+ - \AAAA.BBBB
+ - \AAAA.BBBB.CCCC
+ - \AAAA.BBBB.CCCC.DDDD
+ - \AAAA.BBBB.CCCC.DDDD.MET0 <- Method definition
+
+ Depending on where the method invocation is done, the method definition
+ referenced changes. If the method call "MET0" is done from
+ \AAAA.BBBB.CCCC:
+ 1. Identify which pathnames end with "MET0":
+ - \MET0 <- Device definition
+ - \AAAA.MET0 <- Method definition
+ - \AAAA.BBBB.CCCC.DDDD.MET0 <- Method definition
+ 2. Resolve the method invocation:
+ - \AAAA.MET0 <- Method definition
+ 3. \AAAA.MET0 is a method definition, so return the corresponding
+ reference node.
+
+ @param [in] RawAbsolutePathFStream Forward stream pointing to a raw
+ absolute path.
+ The stream must not be at its end.
+ @param [in] RawPathNameBStream Backward stream pointing to a raw
+ pathname. This raw pathname is the
+ raw NameString of namespace node.
+ The stream must not be at its end.
+ @param [in] NameSpaceRefList List of NameSpaceRef nodes.
+ @param [out] OutNameSpaceRefNode If the two input paths are
+ referencing a method definition,
+ returns the corresponding
+ NameSpaceRef node.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+**/
+STATIC
+EFI_STATUS
+EFIAPI
+AmlFindMethodDefinition (
+ IN CONST AML_STREAM * RawAbsolutePathFStream,
+ IN CONST AML_STREAM * RawPathNameBStream,
+ IN CONST LIST_ENTRY * NameSpaceRefList,
+ OUT AML_NAMESPACE_REF_NODE ** OutNameSpaceRefNode
+ )
+{
+ EFI_STATUS Status;
+
+ LIST_ENTRY * NextLink;
+
+ // To resolve a pathname, scope levels need to be compared.
+ UINT32 NameSegScopeCount;
+ UINT32 PathNameSegScopeCount;
+ UINT32 ProbedScopeCount;
+ UINT32 BestScopeCount;
+
+ AML_STREAM ProbedRawAbsoluteFStream;
+ AML_STREAM ProbedRawAbsoluteBStream;
+
+ AML_NAMESPACE_REF_NODE * ProbedNameSpaceRefNode;
+ AML_NAMESPACE_REF_NODE * BestNameSpaceRefNode;
+
+ if (!IS_STREAM (RawAbsolutePathFStream) ||
+ IS_END_OF_STREAM (RawAbsolutePathFStream) ||
+ !IS_STREAM_FORWARD (RawAbsolutePathFStream) ||
+ ((AmlStreamGetIndex (RawAbsolutePathFStream) &
+ (AML_NAME_SEG_SIZE - 1)) != 0) ||
+ !IS_STREAM (RawPathNameBStream) ||
+ IS_END_OF_STREAM (RawPathNameBStream) ||
+ !IS_STREAM_BACKWARD (RawPathNameBStream) ||
+ ((AmlStreamGetIndex (RawPathNameBStream) &
+ (AML_NAME_SEG_SIZE - 1)) != 0) ||
+ (NameSpaceRefList == NULL) ||
+ (OutNameSpaceRefNode == NULL)) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ DEBUG ((DEBUG_VERBOSE, "AmlMethodParser: Checking absolute name: "));
+ AmlDbgPrintChars (
+ DEBUG_VERBOSE,
+ (CONST CHAR8*)AmlStreamGetCurrPos (RawAbsolutePathFStream),
+ AmlStreamGetMaxBufferSize (RawAbsolutePathFStream)
+ );
+ DEBUG ((DEBUG_VERBOSE, ".\n"));
+
+ BestNameSpaceRefNode = NULL;
+ BestScopeCount = 0;
+ NameSegScopeCount = AmlStreamGetMaxBufferSize (RawAbsolutePathFStream);
+ PathNameSegScopeCount = AmlStreamGetMaxBufferSize (RawPathNameBStream);
+
+ // Iterate through the raw AML absolute path to find the best match.
+ DEBUG ((DEBUG_VERBOSE, "AmlMethodParser: Comparing with: "));
+ NextLink = NameSpaceRefList->ForwardLink;
+ while (NextLink != NameSpaceRefList) {
+ ProbedNameSpaceRefNode = (AML_NAMESPACE_REF_NODE*)NextLink;
+
+ // Print the raw absolute path of the probed node.
+ AmlDbgPrintChars (
+ DEBUG_VERBOSE,
+ ProbedNameSpaceRefNode->RawAbsolutePath,
+ ProbedNameSpaceRefNode->RawAbsolutePathSize
+ );
+ DEBUG ((DEBUG_VERBOSE, "; "));
+
+ // If the raw AML absolute path of the probed node is longer than the
+ // searched pathname, continue.
+ // E.g.: The method call \MET0 cannot resolve to a method defined at
+ // \AAAA.MET0. The method definition is out of scope.
+ if (PathNameSegScopeCount > ProbedNameSpaceRefNode->RawAbsolutePathSize) {
+ NextLink = NextLink->ForwardLink;
+ continue;
+ }
+
+ // Initialize a backward stream for the probed node.
+ // This stream is used to compare the ending of the pathnames.
+ // E.g. if the method searched ends with "MET0", pathnames not ending with
+ // "MET0" should be skipped.
+ Status = AmlStreamInit (
+ &ProbedRawAbsoluteBStream,
+ (UINT8*)ProbedNameSpaceRefNode->RawAbsolutePath,
+ ProbedNameSpaceRefNode->RawAbsolutePathSize,
+ EAmlStreamDirectionBackward
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+
+ // Compare the pathname endings. If they don't match, continue.
+ if (!AmlStreamCmp (
+ RawPathNameBStream,
+ &ProbedRawAbsoluteBStream,
+ AmlStreamGetMaxBufferSize (RawPathNameBStream))) {
+ NextLink = NextLink->ForwardLink;
+ continue;
+ }
+
+ // Initialize a forward stream for the probed node.
+ // This stream is used to count how many scope levels from the root
+ // are common with the probed node. The more there are, the better it is.
+ // E.g.: For the method invocation \AAAA.BBBB.MET0, if there are 2
+ // pathnames ending with MET0:
+ // - \AAAA.MET0 has 1 NameSeg in common with \AAAA.BBBB.MET0
+ // from the root (this is "AAAA");
+ // - \MET0 has 0 NameSeg in common with \AAAA.BBBB.MET0
+ // from the root;
+ // Thus, the best match is \AAAA.MET0.
+ Status = AmlStreamInit (
+ &ProbedRawAbsoluteFStream,
+ (UINT8*)ProbedNameSpaceRefNode->RawAbsolutePath,
+ ProbedNameSpaceRefNode->RawAbsolutePathSize,
+ EAmlStreamDirectionForward
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+
+ // Count how many namespace levels are in common from the root.
+ Status = AmlCompareRawNameString (
+ RawAbsolutePathFStream,
+ &ProbedRawAbsoluteFStream,
+ &ProbedScopeCount
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ if (ProbedScopeCount == NameSegScopeCount) {
+ // This is a perfect match. Exit the loop.
+ BestNameSpaceRefNode = ProbedNameSpaceRefNode;
+ break;
+ } else if (ProbedScopeCount > BestScopeCount) {
+ // The probed node has more scope levels in common than the
+ // last best match. Update the best match.
+ BestScopeCount = ProbedScopeCount;
+ BestNameSpaceRefNode = ProbedNameSpaceRefNode;
+ } else if (ProbedScopeCount == BestScopeCount) {
+ // The probed node has the same number of scope levels in
+ // common as the last best match.
+ if (ProbedScopeCount == 0) {
+ // There was not best match previously. Set it.
+ BestNameSpaceRefNode = ProbedNameSpaceRefNode;
+ } else {
+ // (ProbedScopeCount != 0)
+ // If there is an equivalent candidate, the best has the shortest
+ // absolute path. Indeed, a similar ProbedScopeCount and a longer
+ // path means the definition is out of the scope.
+ // E.g.: For the method invocation \AAAA.BBBB.MET0, if there are 2
+ // pathnames ending with MET0:
+ // - \AAAA.MET0 has 1 NameSegs in common with \AAAA.BBBB.MET0
+ // from the root (this is "AAAA");
+ // - \AAAA.CCCC.MET0 has 1 NameSegs in common with
+ // \AAAA.BBBB.MET0 from the root (this is "AAAA");
+ // As \AAAA.CCCC.MET0 is longer than \AAAA.MET0, it means that
+ // the pathname could have matched on more NameSegs, but it
+ // didn't because it is out of scope.
+ // Thus, the best match is \AAAA.MET0.
+ if (AmlStreamGetIndex (&ProbedRawAbsoluteFStream) <
+ BestNameSpaceRefNode->RawAbsolutePathSize) {
+ BestScopeCount = ProbedScopeCount;
+ BestNameSpaceRefNode = ProbedNameSpaceRefNode;
+ } else if (AmlStreamGetIndex (&ProbedRawAbsoluteFStream) ==
+ BestNameSpaceRefNode->RawAbsolutePathSize) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+ }
+ }
+
+ NextLink = NextLink->ForwardLink;
+ }
+
+ DEBUG ((DEBUG_VERBOSE, "\n"));
+
+ // Check whether the BestNameSpaceRefNode is a method definition.
+ if (BestNameSpaceRefNode != NULL) {
+ if (AmlIsMethodDefinitionNode (BestNameSpaceRefNode->NodeRef)) {
+ *OutNameSpaceRefNode = BestNameSpaceRefNode;
+ } else if (AmlNodeCompareOpCode (
+ BestNameSpaceRefNode->NodeRef,
+ AML_ALIAS_OP, 0)) {
+ // The path matches an alias. Resolve the alias and check whether
+ // this is a method defintion.
+ Status = AmlResolveAliasMethod (
+ BestNameSpaceRefNode->NodeRef,
+ NameSpaceRefList,
+ OutNameSpaceRefNode
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+ }
+ } else {
+ // If no, return NULL, even if a matching pathname has been found.
+ *OutNameSpaceRefNode = NULL;
+ }
+
+ return EFI_SUCCESS;
+}
+
+/** Check whether a pathname is a method invocation.
+
+ If there is a matching method definition, returns the corresponding
+ NameSpaceRef node.
+
+ To do so, the NameSpaceRefList is keeping track of every namespace node
+ and its raw AML absolute path.
+ To check whether a pathname is a method invocation, a corresponding raw
+ absolute pathname is built. This raw absolute pathname is then compared
+ to the list of available pathnames. If a pathname defining a method
+ matches the scope of the input pathname, return.
+
+ @param [in] ParentNode Parent node. Node to which the node to be
+ created will be attached.
+ @param [in] FStream Forward stream pointing to the NameString
+ to find.
+ @param [in] NameSpaceRefList List of NameSpaceRef nodes.
+ @param [out] OutNameSpaceRefNode If the NameString pointed by FStream is
+ a method invocation, OutNameSpaceRefNode
+ contains the NameSpaceRef corresponding
+ to the method definition.
+ NULL otherwise.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+**/
+EFI_STATUS
+EFIAPI
+AmlIsMethodInvocation (
+ IN CONST AML_NODE_HEADER * ParentNode,
+ IN CONST AML_STREAM * FStream,
+ IN CONST LIST_ENTRY * NameSpaceRefList,
+ OUT AML_NAMESPACE_REF_NODE ** OutNameSpaceRefNode
+ )
+{
+ EFI_STATUS Status;
+
+ AML_STREAM RawPathNameBStream;
+ AML_STREAM RawAbsolutePathFStream;
+
+ AML_STREAM RawAbsolutePathBStream;
+ UINT8 * RawAbsolutePathBuffer;
+ UINT32 RawAbsolutePathBufferSize;
+
+ AML_NAMESPACE_REF_NODE * NameSpaceRefNode;
+
+ if ((!IS_AML_OBJECT_NODE (ParentNode) &&
+ !IS_AML_ROOT_NODE (ParentNode)) ||
+ !IS_STREAM (FStream) ||
+ IS_END_OF_STREAM (FStream) ||
+ !IS_STREAM_FORWARD (FStream) ||
+ (NameSpaceRefList == NULL) ||
+ (OutNameSpaceRefNode == NULL)) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ // There cannot be a method invocation in a field list. Return.
+ if (AmlNodeHasAttribute (
+ (CONST AML_OBJECT_NODE*)ParentNode,
+ AML_HAS_FIELD_LIST)) {
+ *OutNameSpaceRefNode = NULL;
+ return EFI_SUCCESS;
+ }
+
+ // Allocate memory for the raw absolute path.
+ RawAbsolutePathBufferSize = MAX_AML_NAMESTRING_SIZE;
+ RawAbsolutePathBuffer = AllocateZeroPool (RawAbsolutePathBufferSize);
+ if (RawAbsolutePathBuffer == NULL) {
+ ASSERT (0);
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ // Initialize a backward stream to get the raw absolute path.
+ Status = AmlStreamInit (
+ &RawAbsolutePathBStream,
+ RawAbsolutePathBuffer,
+ RawAbsolutePathBufferSize,
+ EAmlStreamDirectionBackward
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ goto exit_handler;
+ }
+
+ // Build the raw AML absolute path of the namespace node.
+ Status = AmlBuildRawMethodAbsolutePath (
+ ParentNode,
+ FStream,
+ &RawAbsolutePathBStream
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ goto exit_handler;
+ }
+
+ // If this is the root path: it cannot be a method invocation. Just return.
+ if (AmlStreamGetIndex (&RawAbsolutePathBStream) == 0) {
+ DEBUG ((
+ DEBUG_VERBOSE,
+ "AmlMethodParser: "
+ "Root node cannot be a method invocation\n"
+ ));
+ *OutNameSpaceRefNode = NULL;
+ Status = EFI_SUCCESS;
+ goto exit_handler;
+ }
+
+ // Create a forward stream for the raw absolute path.
+ // This forward stream only contains the raw absolute path with
+ // no extra free space.
+ Status = AmlStreamInit (
+ &RawAbsolutePathFStream,
+ AmlStreamGetCurrPos (&RawAbsolutePathBStream),
+ AmlStreamGetIndex (&RawAbsolutePathBStream),
+ EAmlStreamDirectionForward
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ goto exit_handler;
+ }
+
+ // Create a backward stream for the node name.
+ Status = AmlInitRawPathBStream (
+ FStream,
+ &RawPathNameBStream
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+
+ // Go through the NameSpaceRefList elements to check for
+ // a corresponding method definition.
+ NameSpaceRefNode = NULL;
+ Status = AmlFindMethodDefinition (
+ &RawAbsolutePathFStream,
+ &RawPathNameBStream,
+ NameSpaceRefList,
+ &NameSpaceRefNode
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ goto exit_handler;
+ }
+
+#if !defined(MDEPKG_NDEBUG)
+ // Print whether a method definition has been found.
+ if (NameSpaceRefNode != NULL) {
+ DEBUG ((
+ DEBUG_VERBOSE,
+ "AmlMethodParser: Corresponding method definition: "
+ ));
+ AmlDbgPrintChars (
+ DEBUG_VERBOSE,
+ NameSpaceRefNode->RawAbsolutePath,
+ NameSpaceRefNode->RawAbsolutePathSize
+ );
+ DEBUG ((DEBUG_VERBOSE, ".\n"));
+
+ } else {
+ DEBUG ((DEBUG_VERBOSE, "AmlMethodParser: No method definition found.\n"));
+ }
+#endif // MDEPKG_NDEBUG
+
+ *OutNameSpaceRefNode = NameSpaceRefNode;
+
+exit_handler:
+ // Free allocated memory.
+ FreePool (RawAbsolutePathBuffer);
+ return Status;
+}
+
+/** Create a namespace reference node and add it to the NameSpaceRefList.
+
+ When a namespace node is encountered, the namespace it defines must be
+ associated to the node. This allow to keep track of the nature of each
+ name present in the AML namespace.
+
+ In the end, this allows to recognize method invocations and parse the right
+ number of arguments after the method name.
+
+ @param [in] Node Namespace node.
+ @param [in, out] NameSpaceRefList List of namespace reference nodes.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+**/
+EFI_STATUS
+EFIAPI
+AmlAddNameSpaceReference (
+ IN CONST AML_OBJECT_NODE * Node,
+ IN OUT LIST_ENTRY * NameSpaceRefList
+ )
+{
+ EFI_STATUS Status;
+ AML_NAMESPACE_REF_NODE * NameSpaceRefNode;
+
+ AML_STREAM NodeNameFStream;
+ EAML_PARSE_INDEX NameIndex;
+ CONST AML_DATA_NODE * NameNode;
+
+ AML_STREAM RawAbsolutePathBStream;
+ UINT32 RawAbsolutePathBStreamSize;
+
+ CHAR8 * AbsolutePathBuffer;
+ UINT32 AbsolutePathBufferSize;
+
+ CONST AML_NODE_HEADER * ParentNode;
+
+ if (!AmlNodeHasAttribute (Node, AML_IN_NAMESPACE) ||
+ (NameSpaceRefList == NULL)) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ // Allocate a buffer to get the raw AML absolute pathname of the
+ // namespace node.
+ AbsolutePathBufferSize = MAX_AML_NAMESTRING_SIZE;
+ AbsolutePathBuffer = AllocateZeroPool (AbsolutePathBufferSize);
+ if (AbsolutePathBuffer == NULL) {
+ ASSERT (0);
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ Status = AmlStreamInit (
+ &RawAbsolutePathBStream,
+ (UINT8*)AbsolutePathBuffer,
+ AbsolutePathBufferSize,
+ EAmlStreamDirectionBackward
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ Status = EFI_INVALID_PARAMETER;
+ goto exit_handler;
+ }
+
+ // Get the index where the name of the Node is stored in its
+ // fixed list of arguments.
+ Status = AmlNodeGetNameIndex (Node, &NameIndex);
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ Status = EFI_INVALID_PARAMETER;
+ goto exit_handler;
+ }
+
+ // Get the Node name.
+ NameNode = (CONST AML_DATA_NODE*)AmlGetFixedArgument (
+ (AML_OBJECT_NODE*)Node,
+ NameIndex
+ );
+ if (!IS_AML_DATA_NODE (NameNode) ||
+ (NameNode->DataType != EAmlNodeDataTypeNameString)) {
+ ASSERT (0);
+ Status = EFI_INVALID_PARAMETER;
+ goto exit_handler;
+ }
+
+ // Initialize a stream on the node name of the namespace node.
+ // This is an AML NameString.
+ Status = AmlStreamInit (
+ &NodeNameFStream,
+ NameNode->Buffer,
+ NameNode->Size,
+ EAmlStreamDirectionForward
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ Status = EFI_INVALID_PARAMETER;
+ goto exit_handler;
+ }
+
+ ParentNode = AmlGetParent ((AML_NODE_HEADER*)Node);
+ if (ParentNode == NULL) {
+ ASSERT (0);
+ Status = EFI_INVALID_PARAMETER;
+ goto exit_handler;
+ }
+
+ // Build the raw AML absolute path of the namespace node.
+ Status = AmlBuildRawMethodAbsolutePath (
+ ParentNode,
+ &NodeNameFStream,
+ &RawAbsolutePathBStream
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ goto exit_handler;
+ }
+
+ RawAbsolutePathBStreamSize = AmlStreamGetIndex (&RawAbsolutePathBStream);
+ // This is the root path: this cannot be a method invocation.
+ if (RawAbsolutePathBStreamSize == 0) {
+ Status = EFI_SUCCESS;
+ goto exit_handler;
+ }
+
+ // Create a NameSpace reference node.
+ Status = AmlCreateMethodRefNode (
+ Node,
+ (CONST CHAR8*)AmlStreamGetCurrPos (&RawAbsolutePathBStream),
+ RawAbsolutePathBStreamSize,
+ &NameSpaceRefNode
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ goto exit_handler;
+ }
+
+ // Add the created NameSpaceRefNode to the list.
+ InsertTailList (NameSpaceRefList, &NameSpaceRefNode->Link);
+
+ DEBUG ((
+ DEBUG_VERBOSE,
+ "AmlMethodParser: Adding namespace reference with name:\n"
+ ));
+ AmlDbgPrintChars (
+ DEBUG_VERBOSE,
+ (CONST CHAR8*)AmlStreamGetCurrPos (&RawAbsolutePathBStream),
+ AmlStreamGetIndex (&RawAbsolutePathBStream)
+ );
+ DEBUG ((DEBUG_VERBOSE, "\n"));
+
+exit_handler:
+ // Free allocated memory.
+ FreePool (AbsolutePathBuffer);
+
+ return Status;
+}
+
+/** Create a method invocation node.
+
+ The AML grammar does not attribute an OpCode/SubOpCode couple for
+ method invocations. This library is representing method invocations
+ as if they had one.
+
+ The AML encoding for method invocations in the ACPI specification 6.3 is:
+ MethodInvocation := NameString TermArgList
+ In this library, it is:
+ MethodInvocation := MethodInvocationOp NameString ArgumentCount TermArgList
+ ArgumentCount := ByteData
+
+ When computing the size of a tree or serializing it, the additional data is
+ not taken into account (i.e. the MethodInvocationOp and the ArgumentCount).
+
+ Method invocation nodes have the AML_METHOD_INVOVATION attribute.
+
+ @param [in] NameSpaceRefNode NameSpaceRef node pointing to the
+ the definition of the invoked
+ method.
+ @param [in] MethodInvocationName Data node containing the method
+ invocation name.
+ @param [out] MethodInvocationNodePtr Created method invocation node.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+ @retval EFI_OUT_OF_RESOURCES Could not allocate memory.
+**/
+EFI_STATUS
+EFIAPI
+AmlCreateMethodInvocationNode (
+ IN CONST AML_NAMESPACE_REF_NODE * NameSpaceRefNode,
+ IN AML_DATA_NODE * MethodInvocationName,
+ OUT AML_OBJECT_NODE ** MethodInvocationNodePtr
+ )
+{
+ EFI_STATUS Status;
+
+ UINT8 ArgCount;
+ AML_DATA_NODE * ArgCountNode;
+ AML_NODE_HEADER ** FixedArgs;
+ AML_OBJECT_NODE * MethodDefinitionNode;
+ AML_OBJECT_NODE * MethodInvocationNode;
+
+ if ((NameSpaceRefNode == NULL) ||
+ !AmlIsMethodDefinitionNode (NameSpaceRefNode->NodeRef) ||
+ !IS_AML_DATA_NODE (MethodInvocationName) ||
+ (MethodInvocationName->DataType != EAmlNodeDataTypeNameString) ||
+ (MethodInvocationNodePtr == NULL)) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ // Get the number of arguments of the method.
+ MethodDefinitionNode = (AML_OBJECT_NODE*)NameSpaceRefNode->NodeRef;
+ FixedArgs = MethodDefinitionNode->FixedArgs;
+ // The method definition is an actual method definition.
+ if (AmlNodeCompareOpCode (MethodDefinitionNode, AML_METHOD_OP, 0)) {
+ // Cf ACPI 6.3 specification:
+ // DefMethod := MethodOp PkgLength NameString MethodFlags TermList
+ // MethodOp := 0x14
+ // MethodFlags := ByteData bit 0-2: ArgCount (0-7)
+ // bit 3: SerializeFlag
+ // 0 NotSerialized
+ // 1 Serialized
+ // bit 4-7: SyncLevel (0x00-0x0f)
+
+ // Read the MethodFlags to decode the ArgCount.
+ ArgCountNode = (AML_DATA_NODE*)FixedArgs[EAmlParseIndexTerm1];
+ ArgCount = *((UINT8*)ArgCountNode->Buffer) & 0x7;
+ } else if (AmlNodeCompareOpCode (MethodDefinitionNode, AML_EXTERNAL_OP, 0)) {
+ // The method definition is an external statement.
+ // Cf ACPI 6.3 specification:
+ // DefExternal := ExternalOp NameString ObjectType ArgumentCount
+ // ExternalOp := 0x15
+ // ObjectType := ByteData
+ // ArgumentCount := ByteData (0 – 7)
+
+ // Read the ArgumentCount.
+ ArgCountNode = (AML_DATA_NODE*)FixedArgs[EAmlParseIndexTerm2];
+ ArgCount = *((UINT8*)ArgCountNode->Buffer);
+ } else {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ // Create the object node for the method invocation.
+ // MethodInvocation := MethodInvocationOp NameString ArgumentCount
+ // MethodInvocationOp := Pseudo Opcode for Method Invocation
+ // NameString := Method Name
+ // ArgumentCount := ByteData (0 – 7)
+ Status = AmlCreateObjectNode (
+ AmlGetByteEncodingByOpCode (AML_METHOD_INVOC_OP, 0),
+ 0,
+ &MethodInvocationNode
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ return Status;
+ }
+
+ // The first fixed argument is the method name.
+ Status = AmlSetFixedArgument (
+ MethodInvocationNode,
+ EAmlParseIndexTerm0,
+ (AML_NODE_HEADER*)MethodInvocationName
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ goto error_handler;
+ }
+
+ // Create a data node holding the number of arguments
+ // of the method invocation.
+ ArgCountNode = NULL;
+ Status = AmlCreateDataNode (
+ EAmlNodeDataTypeUInt,
+ &ArgCount,
+ sizeof (UINT8),
+ &ArgCountNode
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ goto error_handler;
+ }
+
+ // The second fixed argument is the number of arguments.
+ Status = AmlSetFixedArgument (
+ MethodInvocationNode,
+ EAmlParseIndexTerm1,
+ (AML_NODE_HEADER*)ArgCountNode
+ );
+ if (EFI_ERROR (Status)) {
+ ASSERT (0);
+ goto error_handler;
+ }
+
+ *MethodInvocationNodePtr = MethodInvocationNode;
+ return Status;
+
+error_handler:
+ // Delete the sub-tree: the method invocation name is already attached.
+ AmlDeleteTree ((AML_NODE_HEADER*)MethodInvocationNode);
+ if (ArgCountNode != NULL) {
+ AmlDeleteNode ((AML_NODE_HEADER*)ArgCountNode);
+ }
+
+ return Status;
+}
+
+/** Get the number of arguments of a method invocation node.
+
+ This function also allow to identify whether a node is a method invocation
+ node. If the input node is not a method invocation node, just return.
+
+ @param [in] MethodInvocationNode Method invocation node.
+ @param [out] IsMethodInvocation Boolean stating whether the input
+ node is a method invocation.
+ @param [out] ArgCount Number of arguments of the method
+ invocation.
+ Set to 0 if MethodInvocationNode
+ is not a method invocation.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_BUFFER_TOO_SMALL No space left in the buffer.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+ @retval EFI_OUT_OF_RESOURCES Could not allocate memory.
+*/
+EFI_STATUS
+EFIAPI
+AmlGetMethodInvocationArgCount (
+ IN CONST AML_OBJECT_NODE * MethodInvocationNode,
+ OUT BOOLEAN * IsMethodInvocation,
+ OUT UINT8 * ArgCount
+ )
+{
+ AML_DATA_NODE * NumArgsNode;
+
+ if (!IS_AML_NODE_VALID (MethodInvocationNode) ||
+ (IsMethodInvocation == NULL) ||
+ (ArgCount == NULL)) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+
+ // Check whether MethodInvocationNode is a method invocation.
+ if (!AmlNodeCompareOpCode (MethodInvocationNode, AML_METHOD_INVOC_OP, 0)) {
+ *IsMethodInvocation = FALSE;
+ *ArgCount = 0;
+ return EFI_SUCCESS;
+ }
+
+ // MethodInvocation := MethodInvocationOp NameString ArgumentCount
+ // MethodInvocationOp := Pseudo Opcode for Method Invocation
+ // NameString := Method Name
+ // ArgumentCount := ByteData (0 - 7)
+ NumArgsNode = (AML_DATA_NODE*)AmlGetFixedArgument (
+ (AML_OBJECT_NODE*)MethodInvocationNode,
+ EAmlParseIndexTerm1
+ );
+ if (!IS_AML_NODE_VALID (NumArgsNode) ||
+ (NumArgsNode->Buffer == NULL) ||
+ (NumArgsNode->DataType != EAmlNodeDataTypeUInt) ||
+ (NumArgsNode->Size != 1)) {
+ ASSERT (0);
+ return EFI_INVALID_PARAMETER;
+ }
+ *ArgCount = *NumArgsNode->Buffer;
+
+ *IsMethodInvocation = TRUE;
+ return EFI_SUCCESS;
+}
diff --git a/DynamicTablesPkg/Library/Common/AmlLib/Parser/AmlMethodParser.h b/DynamicTablesPkg/Library/Common/AmlLib/Parser/AmlMethodParser.h
new file mode 100644
index 0000000000..b082f2debd
--- /dev/null
+++ b/DynamicTablesPkg/Library/Common/AmlLib/Parser/AmlMethodParser.h
@@ -0,0 +1,188 @@
+/** @file
+ AML Method Parser.
+
+ Copyright (c) 2019 - 2020, Arm Limited. All rights reserved.<BR>
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#ifndef AML_METHOD_PARSER_H_
+#define AML_METHOD_PARSER_H_
+
+#include <AmlNodeDefines.h>
+#include <Stream/AmlStream.h>
+
+/** AML namespace reference node.
+
+ Namespace reference nodes allow to associate an AML absolute pathname
+ to the tree node defining this object in the namespace.
+
+ Namespace reference nodes are stored in a separate list. They are not part of
+ the tree.
+*/
+typedef struct AmlNameSpaceRefNode {
+ /// Double linked list.
+ /// This must be the first field in this structure.
+ LIST_ENTRY Link;
+
+ /// Node part of the AML namespace. It must have the AML_IN_NAMESPACE
+ /// attribute.
+ CONST AML_OBJECT_NODE * NodeRef;
+
+ /// Raw AML absolute pathname of the NodeRef.
+ /// This is a raw AML NameString (cf AmlNameSpace.c: A concatenated list
+ /// of 4 chars long names. The dual/multi NameString prefix have been
+ /// stripped.).
+ CONST CHAR8 * RawAbsolutePath;
+
+ /// Size of the raw AML absolute pathname buffer.
+ UINT32 RawAbsolutePathSize;
+} AML_NAMESPACE_REF_NODE;
+
+/** Delete a list of namespace reference nodes.
+
+ @param [in] NameSpaceRefList List of namespace reference nodes.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+**/
+EFI_STATUS
+EFIAPI
+AmlDeleteNameSpaceRefList (
+ IN LIST_ENTRY * NameSpaceRefList
+ );
+
+
+#if !defined (MDEPKG_NDEBUG)
+/** Print the list of raw absolute paths of the NameSpace reference list.
+
+ @param [in] NameSpaceRefList List of NameSpace reference nodes.
+**/
+VOID
+EFIAPI
+AmlDbgPrintNameSpaceRefList (
+ IN CONST LIST_ENTRY * NameSpaceRefList
+ );
+
+#endif // MDEPKG_NDEBUG
+
+/** Check whether a pathname is a method invocation.
+
+ If there is a matching method definition, returns the corresponding
+ NameSpaceRef node.
+
+ To do so, the NameSpaceRefList is keeping track of every namespace node
+ and its raw AML absolute path.
+ To check whether a pathname is a method invocation, a corresponding raw
+ absolute pathname is built. This raw absolute pathname is then compared
+ to the list of available pathnames. If a pathname defining a method
+ matches the scope of the input pathname, return.
+
+ @param [in] ParentNode Parent node. Node to which the node to be
+ created will be attached.
+ @param [in] FStream Forward stream pointing to the NameString
+ to find.
+ @param [in] NameSpaceRefList List of NameSpaceRef nodes.
+ @param [out] OutNameSpaceRefNode If the NameString pointed by FStream is
+ a method invocation, OutNameSpaceRefNode
+ contains the NameSpaceRef corresponding
+ to the method definition.
+ NULL otherwise.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+**/
+EFI_STATUS
+EFIAPI
+AmlIsMethodInvocation (
+ IN CONST AML_NODE_HEADER * ParentNode,
+ IN CONST AML_STREAM * FStream,
+ IN CONST LIST_ENTRY * NameSpaceRefList,
+ OUT AML_NAMESPACE_REF_NODE ** OutNameSpaceRefNode
+ );
+
+/** Create a namespace reference node and add it to the NameSpaceRefList.
+
+ When a namespace node is encountered, the namespace it defines must be
+ associated to the node. This allow to keep track of the nature of each
+ name present in the AML namespace.
+
+ In the end, this allows to recognize method invocations and parse the right
+ number of arguments after the method name.
+
+ @param [in] Node Namespace node.
+ @param [in, out] NameSpaceRefList List of namespace reference nodes.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+**/
+EFI_STATUS
+EFIAPI
+AmlAddNameSpaceReference (
+ IN CONST AML_OBJECT_NODE * Node,
+ IN OUT LIST_ENTRY * NameSpaceRefList
+ );
+
+/** Create a method invocation node.
+
+ The AML grammar does not attribute an OpCode/SubOpCode couple for
+ method invocations. This library is representing method invocations
+ as if they had one.
+
+ The AML encoding for method invocations in the ACPI specification 6.3 is:
+ MethodInvocation := NameString TermArgList
+ In this library, it is:
+ MethodInvocation := MethodInvocationOp NameString ArgumentCount TermArgList
+ ArgumentCount := ByteData
+
+ When computing the size of a tree or serializing it, the additional data is
+ not taken into account (i.e. the MethodInvocationOp and the ArgumentCount).
+
+ Method invocation nodes have the AML_METHOD_INVOVATION attribute.
+
+ @param [in] NameSpaceRefNode NameSpaceRef node pointing to the
+ the definition of the invoked
+ method.
+ @param [in] MethodInvocationName Data node containing the method
+ invocation name.
+ @param [out] MethodInvocationNodePtr Created method invocation node.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+ @retval EFI_OUT_OF_RESOURCES Could not allocate memory.
+**/
+EFI_STATUS
+EFIAPI
+AmlCreateMethodInvocationNode (
+ IN CONST AML_NAMESPACE_REF_NODE * NameSpaceRefNode,
+ IN AML_DATA_NODE * MethodInvocationName,
+ OUT AML_OBJECT_NODE ** MethodInvocationNodePtr
+ );
+
+/** Get the number of arguments of a method invocation node.
+
+ This function also allow to identify whether a node is a method invocation
+ node. If the input node is not a method invocation node, just return.
+
+ @param [in] MethodInvocationNode Method invocation node.
+ @param [out] IsMethodInvocation Boolean stating whether the input
+ node is a method invocation.
+ @param [out] ArgCount Number of arguments of the method
+ invocation.
+ Set to 0 if MethodInvocationNode
+ is not a method invocation.
+
+ @retval EFI_SUCCESS The function completed successfully.
+ @retval EFI_BUFFER_TOO_SMALL No space left in the buffer.
+ @retval EFI_INVALID_PARAMETER Invalid parameter.
+ @retval EFI_OUT_OF_RESOURCES Could not allocate memory.
+*/
+EFI_STATUS
+EFIAPI
+AmlGetMethodInvocationArgCount (
+ IN CONST AML_OBJECT_NODE * MethodInvocationNode,
+ OUT BOOLEAN * IsMethodInvocation,
+ OUT UINT8 * ArgCount
+ );
+
+#endif // AML_METHOD_PARSER_H_