StandaloneMmPkg: Fix ECC error 4002 in StandaloneMmCpu

Bugzilla: 3150 (https://bugzilla.tianocore.org/show_bug.cgi?id=3150)

Fix the ECC reported error "[4002] Function header doesn't exist".

Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
Acked-by: Jiewen Yao <Jiewen.yao@intel.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
Reviewed-by: Liming Gao <gaoliming@byosoft.com.cn>

StandaloneMmPkg/Drivers/StandaloneMmCpu/AArch64/EventHandle.c

@@ -196,10 +196,13 @@ MmFoundationEntryRegister (
   This function is the main entry point for an MM handler dispatch
   or communicate-based callback.
 
-  @param  DispatchHandle  The unique handle assigned to this handler by MmiHandlerRegister().
+  @param  DispatchHandle  The unique handle assigned to this handler by
-  @param  Context         Points to an optional handler context which was specified when the handler was registered.
+                          MmiHandlerRegister().
+  @param  Context         Points to an optional handler context which was
+                          specified when the handler was registered.
   @param  CommBuffer      A pointer to a collection of data in memory that will
-                          be conveyed from a non-MM environment into an MM environment.
+                          be conveyed from a non-MM environment into an
+                          MM environment.
   @param  CommBufferSize  The size of the CommBuffer.
 
   @return Status Code

StandaloneMmPkg/Drivers/StandaloneMmCpu/AArch64/StandaloneMmCpu.c

@@ -44,6 +44,16 @@ EFI_MM_SYSTEM_TABLE *mMmst = NULL;
 //
 STATIC EFI_HANDLE            mMmCpuHandle = NULL;
 
+/** Returns the HOB data for the matching HOB GUID.
+
+  @param  [in]  HobList  Pointer to the HOB list.
+  @param  [in]  HobGuid  The GUID for the HOB.
+  @param  [out] HobData  Pointer to the HOB data.
+
+  @retval  EFI_SUCCESS            The function completed successfully.
+  @retval  EFI_INVALID_PARAMETER  Invalid parameter.
+  @retval  EFI_NOT_FOUND          Could not find HOB with matching GUID.
+**/
 EFI_STATUS
 GetGuidedHobData (
   IN  VOID *HobList,
@@ -70,9 +80,20 @@ GetGuidedHobData (
   return EFI_SUCCESS;
 }
 
+/** Entry point for the Standalone MM CPU driver.
+
+  @param  [in]  ImageHandle   Unused. Not actual image handle.
+  @param  [in]  SystemTable   Pointer to MM System table.
+
+  @retval  EFI_SUCCESS            The function completed successfully.
+  @retval  EFI_INVALID_PARAMETER  Invalid parameter.
+  @retval  EFI_OUT_OF_RESOURCES   Out of resources.
+  @retval  EFI_NOT_FOUND          Failed to find the HOB for the CPU
+                                  driver endpoint descriptor.
+**/
 EFI_STATUS
 StandaloneMmCpuInitialize (
-  IN EFI_HANDLE         ImageHandle,  // not actual imagehandle
+  IN EFI_HANDLE            ImageHandle,  // not actual imagehandle
   IN EFI_MM_SYSTEM_TABLE   *SystemTable  // not actual systemtable
   )
 {

StandaloneMmPkg/Drivers/StandaloneMmCpu/AArch64/StandaloneMmCpu.h

@@ -2,7 +2,7 @@
   Private header with declarations and definitions specific to the MM Standalone
   CPU driver
 
-  Copyright (c) 2017 - 2018, ARM Limited. All rights reserved.
+  Copyright (c) 2017 - 2021, Arm Limited. All rights reserved.
   SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
@@ -33,6 +33,19 @@ extern EFI_MMRAM_DESCRIPTOR          mNsCommBuffer;
 extern MP_INFORMATION_HOB_DATA       *mMpInformationHobData;
 extern EFI_MM_CONFIGURATION_PROTOCOL mMmConfig;
 
+/**
+  The PI Standalone MM entry point for the TF-A CPU driver.
+
+  @param  [in] EventId            The event Id.
+  @param  [in] CpuNumber          The CPU number.
+  @param  [in] NsCommBufferAddr   Address of the NS common buffer.
+
+  @retval   EFI_SUCCESS             Success.
+  @retval   EFI_INVALID_PARAMETER   A parameter was invalid.
+  @retval   EFI_ACCESS_DENIED       Access not permitted.
+  @retval   EFI_OUT_OF_RESOURCES    Out of resources.
+  @retval   EFI_UNSUPPORTED         Operation not supported.
+**/
 EFI_STATUS
 PiMmStandaloneArmTfCpuDriverEntry (
   IN UINTN EventId,
@@ -40,6 +53,22 @@ PiMmStandaloneArmTfCpuDriverEntry (
   IN UINTN NsCommBufferAddr
   );
 
+/**
+  This function is the main entry point for an MM handler dispatch
+  or communicate-based callback.
+
+  @param  DispatchHandle  The unique handle assigned to this handler by
+                          MmiHandlerRegister().
+  @param  Context         Points to an optional handler context which was
+                          specified when the handler was registered.
+  @param  CommBuffer      A pointer to a collection of data in memory that will
+                          be conveyed from a non-MM environment into an
+                          MM environment.
+  @param  CommBufferSize  The size of the CommBuffer.
+
+  @return Status Code
+
+**/
 EFI_STATUS
 EFIAPI
 PiMmCpuTpFwRootMmiHandler (