[PATCH 3/4] MdeModulePkg/DxeIpl: Introduce PCD PcdUse5LevelPageTable

["Ni, Ray" <ray.ni@intel.com>]

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2008

The PCD indicates if 5-Level Paging will be enabled in long mode.
5-Level Paging will not be enabled when the PCD is TRUE but CPU
doesn't support 5-Level Paging.

Signed-off-by: Ray Ni <ray.ni@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
---
 MdeModulePkg/MdeModulePkg.dec | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/MdeModulePkg/MdeModulePkg.dec b/MdeModulePkg/MdeModulePkg.dec
index 12e0bbf579..21388595a9 100644
--- a/MdeModulePkg/MdeModulePkg.dec
+++ b/MdeModulePkg/MdeModulePkg.dec
@@ -1991,6 +1991,13 @@ [PcdsFixedAtBuild, PcdsPatchableInModule, PcdsDynamic, PcdsDynamicEx]
   # @Prompt The address mask when memory encryption is enabled.
   gEfiMdeModulePkgTokenSpaceGuid.PcdPteMemoryEncryptionAddressOrMask|0x0|UINT64|0x30001047
 
+  ## Indicates if 5-Level Paging will be enabled in long mode. 5-Level Paging will not be enabled
+  #  when the PCD is TRUE but CPU doesn't support 5-Level Paging.
+  #   TRUE  - 5-Level Paging will be enabled.<BR>
+  #   FALSE - 5-Level Paging will not be enabled.<BR>
+  # @Prompt Enable 5-Level Paging support in long mode. 
+  gEfiMdeModulePkgTokenSpaceGuid.PcdUse5LevelPageTable|FALSE|BOOLEAN|0x0001105F
+
   ## Capsule In Ram is to use memory to deliver the capsules that will be processed after system
   #  reset.<BR><BR>
   #  This PCD indicates if the Capsule In Ram is supported.<BR>
-- 
2.21.0.windows.1