[RFC PATCH v3 01/43] MdePkg: Create PCDs to be used in support of SEV-ES

["Lendacky, Thomas" <thomas.lendacky@amd.com>]

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198

Two new fixed PCSs are needed to support SEV-ES under OVMF:
  - PcdSecGhcbBase  UINT64 value that is the base address of the GHCB
                    used during the SEC phase.
  - PcdSecGhcbSize  UINT64 value that is the size, in bytes, of the GHCB
                    area used during the SEC phase.

Three new dynamic PCDs are needed to support SEV-ES under OVMF:
  - PcdSevEsIsEnabled: BOOLEAN value used to indicate if SEV-ES is enabled
  - PcdGhcbBase:       UINT64 value that is the base address of the GHCB
                       allocation.
  - PcdGhcbSize:       UINT64 value that is the size, in bytes, of the
                       GHCB allocation (size is dependent on the number of
                       APs).

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao A Wu <hao.a.wu@intel.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 MdeModulePkg/MdeModulePkg.dec | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/MdeModulePkg/MdeModulePkg.dec b/MdeModulePkg/MdeModulePkg.dec
index 41b9e70a1ac8..c3bdfcc80971 100644
--- a/MdeModulePkg/MdeModulePkg.dec
+++ b/MdeModulePkg/MdeModulePkg.dec
@@ -1037,6 +1037,14 @@ [PcdsFixedAtBuild]
   # @Prompt Enable UEFI Stack Guard.
   gEfiMdeModulePkgTokenSpaceGuid.PcdCpuStackGuard|FALSE|BOOLEAN|0x30001055
 
+  ## The base address of the SEC GHCB page.
+  # @Prompt SEC GHCB Base Address
+  gEfiMdeModulePkgTokenSpaceGuid.PcdSecGhcbBase|0|UINT32|0x30001056
+
+  ## The total size of the SEC GHCB page.
+  # @Prompt SEC GHCB Size
+  gEfiMdeModulePkgTokenSpaceGuid.PcdSecGhcbSize|0|UINT32|0x30001057
+
 [PcdsFixedAtBuild, PcdsPatchableInModule]
   ## Dynamic type PCD can be registered callback function for Pcd setting action.
   #  PcdMaxPeiPcdCallBackNumberPerPcdEntry indicates the maximum number of callback function
@@ -2053,6 +2061,21 @@ [PcdsDynamic, PcdsDynamicEx]
   # @Prompt If there is any test key used by the platform.
   gEfiMdeModulePkgTokenSpaceGuid.PcdTestKeyUsed|FALSE|BOOLEAN|0x00030003
 
+  ## This dynamic PCD indicates whether SEV-ES is enabled
+  #   TRUE  - SEV-ES is enabled
+  #   FALSE - SEV-ES is not enabled
+  # @Prompt SEV-ES Status
+  gEfiMdeModulePkgTokenSpaceGuid.PcdSevEsIsEnabled|FALSE|BOOLEAN|0x00030007
+
+  ## This dynamic PCD holds the base address of the GHCB pool allocation.
+  # @Prompt GHCB Pool Base Address
+  gEfiMdeModulePkgTokenSpaceGuid.PcdGhcbBase|0|UINT64|0x00030008
+
+  ## This dynamic PCD holds the total size of the GHCB pool allocation.
+  #  The amount of memory allocated for GHCBs is dependent on the number of APs.
+  # @Prompt GHCB Pool Size
+  gEfiMdeModulePkgTokenSpaceGuid.PcdGhcbSize|0|UINT64|0x00030009
+
 [PcdsDynamicEx]
   ## This dynamic PCD enables the default variable setting.
   #  Its value is the default store ID value. The default value is zero as Standard default.
-- 
2.17.1