diff options
-rw-r--r-- | OvmfPkg/PlatformPei/AmdSev.c | 55 | ||||
-rw-r--r-- | OvmfPkg/PlatformPei/PlatformPei.inf | 2 |
2 files changed, 57 insertions, 0 deletions
diff --git a/OvmfPkg/PlatformPei/AmdSev.c b/OvmfPkg/PlatformPei/AmdSev.c index c60a153a05..9b71f7cf2f 100644 --- a/OvmfPkg/PlatformPei/AmdSev.c +++ b/OvmfPkg/PlatformPei/AmdSev.c @@ -24,6 +24,12 @@ #include "Platform.h"
+STATIC
+UINT64
+GetHypervisorFeature (
+ VOID
+ );
+
/**
Initialize SEV-SNP support if running as an SEV-SNP guest.
@@ -36,12 +42,22 @@ AmdSevSnpInitialize ( {
EFI_PEI_HOB_POINTERS Hob;
EFI_HOB_RESOURCE_DESCRIPTOR *ResourceHob;
+ UINT64 HvFeatures;
+ EFI_STATUS PcdStatus;
if (!MemEncryptSevSnpIsEnabled ()) {
return;
}
//
+ // Query the hypervisor feature using the VmgExit and set the value in the
+ // hypervisor features PCD.
+ //
+ HvFeatures = GetHypervisorFeature ();
+ PcdStatus = PcdSet64S (PcdGhcbHypervisorFeatures, HvFeatures);
+ ASSERT_RETURN_ERROR (PcdStatus);
+
+ //
// Iterate through the system RAM and validate it.
//
for (Hob.Raw = GetHobList (); !END_OF_HOB_LIST (Hob); Hob.Raw = GET_NEXT_HOB (Hob)) {
@@ -92,6 +108,45 @@ SevEsProtocolFailure ( }
/**
+ Get the hypervisor features bitmap
+
+**/
+STATIC
+UINT64
+GetHypervisorFeature (
+ VOID
+ )
+{
+ UINT64 Status;
+ GHCB *Ghcb;
+ MSR_SEV_ES_GHCB_REGISTER Msr;
+ BOOLEAN InterruptState;
+ UINT64 Features;
+
+ Msr.GhcbPhysicalAddress = AsmReadMsr64 (MSR_SEV_ES_GHCB);
+ Ghcb = Msr.Ghcb;
+
+ //
+ // Initialize the GHCB
+ //
+ VmgInit (Ghcb, &InterruptState);
+
+ //
+ // Query the Hypervisor Features.
+ //
+ Status = VmgExit (Ghcb, SVM_EXIT_HYPERVISOR_FEATURES, 0, 0);
+ if ((Status != 0)) {
+ SevEsProtocolFailure (GHCB_TERMINATE_GHCB_GENERAL);
+ }
+
+ Features = Ghcb->SaveArea.SwExitInfo2;
+
+ VmgDone (Ghcb, InterruptState);
+
+ return Features;
+}
+
+/**
This function can be used to register the GHCB GPA.
diff --git a/OvmfPkg/PlatformPei/PlatformPei.inf b/OvmfPkg/PlatformPei/PlatformPei.inf index bada5ea144..3c05b550e4 100644 --- a/OvmfPkg/PlatformPei/PlatformPei.inf +++ b/OvmfPkg/PlatformPei/PlatformPei.inf @@ -62,6 +62,7 @@ MtrrLib
MemEncryptSevLib
PcdLib
+ VmgExitLib
[Pcd]
gUefiOvmfPkgTokenSpaceGuid.PcdOvmfPeiMemFvBase
@@ -107,6 +108,7 @@ gUefiCpuPkgTokenSpaceGuid.PcdCpuApStackSize
gUefiCpuPkgTokenSpaceGuid.PcdSevEsIsEnabled
gEfiMdePkgTokenSpaceGuid.PcdConfidentialComputingGuestAttr
+ gUefiCpuPkgTokenSpaceGuid.PcdGhcbHypervisorFeatures
[FixedPcd]
gEfiMdePkgTokenSpaceGuid.PcdPciExpressBaseAddress
|