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diff --git a/MdePkg/Library/BaseLib/ConvertGuidUuid.c b/MdePkg/Library/BaseLib/ConvertGuidUuid.c
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+++ b/MdePkg/Library/BaseLib/ConvertGuidUuid.c
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+/** @file
+  Convert 128 bit unique identifier between GUID and UUID format.
+
+  Copyright (c) 2024, Arm Limited. All rights reserved.<BR>
+  Copyright (c) Microsoft Corporation.
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+#include "BaseLibInternals.h"
+
+/*******************************************************************************
+
+  UUID (Universally Unique IDentifier), as defined in RFC4122
+  (https://datatracker.ietf.org/doc/html/rfc4122#section-4.1), is a 128-bit number
+  used to uniquely identify information in computer systems.
+
+  UUIDs contains 5 fields:
+  - time_low: 32 bits
+  - time_mid: 16 bits
+  - time_hi_and_version: 16 bits
+  - clock_seq_hi_and_reserved: 8 bits
+  - clock_seq_low: 8 bits
+  - node: 8 bits * 6
+
+  Each field encoded with the Most Significant Byte first (known as network byte
+  order, or big-endian).
+
+  GUID (Globally Unique Identifier), on the other hand, is a 128-bit number used
+  in UEFI environments, which is similar to UUID but has a different byte order
+  in memory. See https://uefi.org/specs/UEFI/2.11/Apx_A_GUID_and_Time_Formats.html
+
+  GUID also contains 5 fields:
+  - TimeLow: 32 bits
+  - TimeMid: 16 bits
+  - TimeHiAndVersion: 16 bits
+  - ClockSeqHighAndReserved: 16 bits
+  - ClockSeqLow: 8 bits
+  - Node: 8 bits * 6
+
+  TimeLow, TimeMid, TimeHighAndVersion fields in the EFI are encoded with the Least
+  Significant Byte first (also known as little-endian).
+
+  Example:
+  Consider the same string representation/registry format for MM communication v2:
+  "378daedc-f06b-4446-8314-40ab933c87a3"
+
+  In UUID format, it is represented as:
+  - Data fields:
+    - time_low: 0x37 0x8d 0xae 0xdc (0x378daedc in big-endian)
+    - time_mid: 0xf0 0x6b (0xf06b in big-endian)
+    - time_hi_and_version: 0x44 0x46 (0x4446 in big-endian)
+    - clock_seq_hi_and_reserved: 0x83
+    - clock_seq_low: 0x14
+    - node: 0x00, 0xab, 0x93, 0x3c, 0x87, 0xa3
+  - Byte representation in memory:
+    - 37 8d ae dc f0 6b 44 46 83 14 40 ab 93 3c 87 a3
+
+  However, in GUID format, it is represented as:
+  - Data fields:
+    - TimeLow: 0xdc 0xae 0x8d 0x37 (0x378daedc in little-endian)
+    - TimeMid: 0x6b 0xf0 (0xf06b in little-endian)
+    - TimeHiAndVersion: 0x46 0x44 (0x4446 in little-endian)
+    - ClockSeqHighAndReserved: 0x83
+    - ClockSeqLow: 0x14
+    - Node: 0x00, 0xab, 0x93, 0x3c, 0x87, 0xa3
+  - Byte representation in memory:
+    - dc ae 8d 37 6b f0 46 44 83 14 40 ab 93 3c 87 a3
+
+*******************************************************************************/
+
+/**
+  This function converts a GUID in UEFI format to a UUID in RFC4122 format.
+
+  The conversion is done by swapping the byte order of the TimeLow, TimeMid, and
+  TimeHiAndVersion fields, while keeping the ClockSeq and Node fields unchanged.
+
+  @param [in] FromGuid  GUID in format to be converted to UUID RFC4122 format.
+  @param [out] ToUuid   Pointer to a GUID structure that will hold the converted
+                        UUID in RFC4122 format.
+**/
+VOID
+EFIAPI
+ConvertGuidToUuid (
+  IN   GUID  *FromGuid,
+  OUT  GUID  *ToUuid
+  )
+{
+  ASSERT (ToUuid != NULL);
+  ASSERT (FromGuid != NULL);
+
+  CopyGuid (ToUuid, FromGuid);
+  ToUuid->Data1 = SwapBytes32 (ToUuid->Data1);
+  ToUuid->Data2 = SwapBytes16 (ToUuid->Data2);
+  ToUuid->Data3 = SwapBytes16 (ToUuid->Data3);
+}
+
+/**
+  This function converts a UUID in RFC4122 format to a GUID in UEFI format.
+
+  The conversion is done by swapping the byte order of the time_low, time_mid, and
+  time_hi_and_version fields, while keeping the ClockSeq and Node fields unchanged.
+  This function is symmetric to ConvertGuidToUuid.
+
+  @param [in] FromUuid  UUID in RFC4122 format to be converted to GUID in UEFI format.
+  @param [out] ToGuid   Pointer to a GUID structure that will hold the converted
+                        GUID in UEFI format.
+**/
+VOID
+EFIAPI
+ConvertUuidToGuid (
+  IN   GUID  *FromUuid,
+  OUT  GUID  *ToGuid
+  )
+{
+  // The conversion is symmetric, so we can use the same function.
+  // The only difference is the order of the parameters.
+  ConvertGuidToUuid (
+    FromUuid,
+    ToGuid
+    );
+}