diff options
| -rw-r--r-- | MdeModulePkg/Universal/PCD/Dxe/Pcd.inf | 11 | ||||
| -rw-r--r-- | MdeModulePkg/Universal/PCD/Pei/Pcd.inf | 8 |
2 files changed, 19 insertions, 0 deletions
diff --git a/MdeModulePkg/Universal/PCD/Dxe/Pcd.inf b/MdeModulePkg/Universal/PCD/Dxe/Pcd.inf index 0b0486737e..5e5bacbcfc 100644 --- a/MdeModulePkg/Universal/PCD/Dxe/Pcd.inf +++ b/MdeModulePkg/Universal/PCD/Dxe/Pcd.inf @@ -1,6 +1,17 @@ #/** @file
# PCD DXE driver manage database contains all dynamic PCD entries initialized in
# PEI phase, DXE phase and produce the implementation of PCD protocol.
+#
+# There are two PCD Protocols as follows:
+# 1) PCD_PROTOCOL
+# It is EDKII implementation which support Dynamic/DynamicEx type Pcds.
+# 2) EFI_PCD_PROTOCOL_PPI
+# It is defined by PI specification 1.2, Vol 3 which only support dynamicEx
+# type Pcd.
+#
+# For dynamicEx type PCD, it is compatible between PCD_PPI and EFI_PEI_PCD_PPI.
+# PCD DXE driver will produce above two protocols at same time.
+#
# PCD database structure is generated at autogen.h/autogen.c in build time.
#
# ////////////////////////////////////////////////////////////////////////////////
diff --git a/MdeModulePkg/Universal/PCD/Pei/Pcd.inf b/MdeModulePkg/Universal/PCD/Pei/Pcd.inf index 075e16aeb4..fc39290911 100644 --- a/MdeModulePkg/Universal/PCD/Pei/Pcd.inf +++ b/MdeModulePkg/Universal/PCD/Pei/Pcd.inf @@ -1,6 +1,14 @@ #/** @file
# PCD PEIM produces PCD database to manage all dynamic PCD in PEI phase and install Pcd Ppi service.
#
+# There are two PCD PPIs as follows:
+# 1) PCD_PPI
+# It is EDKII implementation which support Dynamic/DynamicEx Pcds.
+# 2) EFI_PEI_PCD_PPI
+# It is defined by PI specification 1.2, Vol 3 which only support dynamicEx
+# type Pcd.
+# For dynamicEx type PCD, it is compatible between PCD_PPI and EFI_PEI_PCD_PPI.
+#
# ////////////////////////////////////////////////////////////////////////////////
# // //
# // Introduction of PCD database //
|