OvmfPkg/BaseMemEncryptTdxLib: Add TDX helper library

RFC: https://bugzilla.tianocore.org/show_bug.cgi?id=3429

Add Intel Tdx helper library. The library provides the routines to:
-  set or clear Shared bit for a given memory region.
-  query whether TDX is enabled.

Please be noted, there a lot of duplicated codes for Page Table
operations. These codes should be moved to a common library
(PageTablesLib) so that it is more friendly for review and maintain.
There is a new feature requirement
https://bugzilla.tianocore.org/show_bug.cgi?id=847 which is to
implement the library. After the lib is introduced, BaseMemEncryptTdxLib
will be refactored.

Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Signed-off-by: Min Xu <min.m.xu@intel.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/OvmfPkg/OvmfPkgIa32X64.dsc b/OvmfPkg/OvmfPkgIa32X64.dsc
index bf08e893e0..f16becd028 100644
--- a/OvmfPkg/OvmfPkgIa32X64.dsc
+++ b/OvmfPkg/OvmfPkgIa32X64.dsc
@@ -180,6 +180,7 @@
   VirtioLib|OvmfPkg/Library/VirtioLib/VirtioLib.inf

   LoadLinuxLib|OvmfPkg/Library/LoadLinuxLib/LoadLinuxLib.inf

   MemEncryptSevLib|OvmfPkg/Library/BaseMemEncryptSevLib/DxeMemEncryptSevLib.inf

+  MemEncryptTdxLib|OvmfPkg/Library/BaseMemEncryptTdxLib/BaseMemEncryptTdxLibNull.inf

 !if $(SMM_REQUIRE) == FALSE

   LockBoxLib|OvmfPkg/Library/LockBoxLib/LockBoxBaseLib.inf

 !endif