[PATCH v9 21/32] OvmfPkg/PlatformPei: set PcdConfidentialComputingAttr when SEV is active

["Brijesh Singh" <brijesh.singh@amd.com>]

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3275

The MpInitLib uses the ConfidentialComputingAttr PCD to determine whether
AMD SEV is active so that it can use the VMGEXITs defined in the GHCB
specification to create APs.

Cc: Michael Roth <michael.roth@amd.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Min Xu <min.m.xu@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Suggested-by: Jiewen Yao <jiewen.yao@intel.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
---
 OvmfPkg/PlatformPei/PlatformPei.inf |  1 +
 OvmfPkg/PlatformPei/AmdSev.c        | 15 +++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/OvmfPkg/PlatformPei/PlatformPei.inf b/OvmfPkg/PlatformPei/PlatformPei.inf
index 67eb7aa7166b..233b9494f64b 100644
--- a/OvmfPkg/PlatformPei/PlatformPei.inf
+++ b/OvmfPkg/PlatformPei/PlatformPei.inf
@@ -106,6 +106,7 @@ [Pcd]
   gUefiCpuPkgTokenSpaceGuid.PcdCpuBootLogicalProcessorNumber
   gUefiCpuPkgTokenSpaceGuid.PcdCpuApStackSize
   gUefiCpuPkgTokenSpaceGuid.PcdSevEsIsEnabled
+  gUefiCpuPkgTokenSpaceGuid.PcdConfidentialComputingGuestAttr
 
 [FixedPcd]
   gEfiMdePkgTokenSpaceGuid.PcdPciExpressBaseAddress
diff --git a/OvmfPkg/PlatformPei/AmdSev.c b/OvmfPkg/PlatformPei/AmdSev.c
index 391e7bbb7dbd..5e2c891309d4 100644
--- a/OvmfPkg/PlatformPei/AmdSev.c
+++ b/OvmfPkg/PlatformPei/AmdSev.c
@@ -20,6 +20,7 @@
 #include <Register/Amd/Msr.h>
 #include <Register/Intel/SmramSaveStateMap.h>
 #include <Library/VmgExitLib.h>
+#include <ConfidentialComputingGuestAttr.h>
 
 #include "Platform.h"
 
@@ -342,4 +343,18 @@ AmdSevInitialize (
   // Check and perform SEV-ES initialization if required.
   //
   AmdSevEsInitialize ();
+
+  //
+  // Set the Confidential computing attr PCD to communicate which SEV
+  // technology is active.
+  //
+  if (MemEncryptSevSnpIsEnabled ()) {
+    PcdStatus = PcdSet64S (PcdConfidentialComputingGuestAttr, CCAttrAmdSevSnp);
+  } else if (MemEncryptSevEsIsEnabled ()) {
+    PcdStatus = PcdSet64S (PcdConfidentialComputingGuestAttr, CCAttrAmdSevEs);
+  } else {
+    PcdStatus = PcdSet64S (PcdConfidentialComputingGuestAttr, CCAttrAmdSev);
+  }
+  ASSERT_RETURN_ERROR (PcdStatus);
+
 }
-- 
2.25.1