Commit Graph

3 Commits

Author SHA1 Message Date
Michael Kubacki 731c67e1d7 DynamicTablesPkg: Apply uncrustify changes
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3737

Apply uncrustify changes to .c/.h files in the DynamicTablesPkg package

Cc: Andrew Fish <afish@apple.com>
Cc: Leif Lindholm <leif@nuviainc.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
2021-12-07 17:24:28 +00:00
Pierre Gondois 2dd7dd3952 DynamicTablesPkg: Clear pointer in node creation fcts
The following functions:
- AmlCreateRootNode()
- AmlCreateObjectNode()
- AmlCreateDataNode()
create a node and return it by populating a pointer. This pointer
should only be considered/used if the function returns successfully.
Otherwise, the value stored in this pointer should be ignored.

For their error handling, some other functions assume that this
pointer is reset to NULL if an error occurs during a node creation.
To make this assumption correct, explicitly clear this input pointer.

Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com>
2021-10-08 15:39:42 +00:00
Pierre Gondois bcab901b7c DynamicTablesPkg: AML node definitions
AML has a complex grammar, and this makes runtime modifications
on an AML byte stream difficult. A solution is to parse the AML
bytecode and represent it in a tree data structure, henceforth
called the AML tree.

The AML tree is composite in the sense it has the following node
types:
 - A 'Root node' that represents the root of the AML tree.
 - An 'Object node' that contains the OP Code (AML Encoding).
 - A 'Data node' that contains a data buffer.

The Root node contains the Definition block header (ACPI header)
and a Variable Argument list.
The Object node is composed of an array of Fixed Arguments and
a Variable Argument list.

Fixed arguments can be either Object Nodes or Data nodes. Their
placement (index) in the Fixed Argument array is defined by the
AML encoding of the enclosing Object Node.

Variable arguments can be Object nodes or Data nodes.

Following is a depiction of a typical AML tree:

 (/)                         # Root Node
   \
   |-{(N1)->...}             # Variable Argument list, N1 is
        \                    # an Object Node
         \         /-i       # Child of fixed argument b
          \       /
          |- [a][b][c][d]    # Fixed Arguments
          |- {(e)->(f)->(g)} # Variable Arguments
                \
                 \-h         # Child of variable argument e

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>
2020-08-13 18:00:06 +00:00