diff --git a/MdePkg/Include/Register/Amd/Ghcb.h b/MdePkg/Include/Register/Amd/Ghcb.h
index 029904b1c6..8c5f46e4bb 100644
--- a/MdePkg/Include/Register/Amd/Ghcb.h
+++ b/MdePkg/Include/Register/Amd/Ghcb.h
@@ -55,6 +55,7 @@
 #define SVM_EXIT_AP_RESET_HOLD                  0x80000004ULL
 #define SVM_EXIT_AP_JUMP_TABLE                  0x80000005ULL
 #define SVM_EXIT_SNP_PAGE_STATE_CHANGE          0x80000010ULL
+#define SVM_EXIT_SNP_AP_CREATION                0x80000013ULL
 #define SVM_EXIT_HYPERVISOR_FEATURES            0x8000FFFDULL
 #define SVM_EXIT_UNSUPPORTED                    0x8000FFFFULL
 
@@ -83,6 +84,12 @@
 #define IOIO_SEG_ES         0
 #define IOIO_SEG_DS         (BIT11 | BIT10)
 
+//
+// AP Creation Information
+//
+#define SVM_VMGEXIT_SNP_AP_CREATE_ON_INIT  0
+#define SVM_VMGEXIT_SNP_AP_CREATE          1
+#define SVM_VMGEXIT_SNP_AP_DESTROY         2
 
 typedef PACKED struct {
   UINT8                  Reserved1[203];
@@ -195,4 +202,81 @@ typedef struct {
   SNP_PAGE_STATE_ENTRY   Entry[SNP_PAGE_STATE_MAX_ENTRY];
 } SNP_PAGE_STATE_CHANGE_INFO;
 
+//
+// SEV-ES save area mapping structures used for SEV-SNP AP Creation.
+// Only the fields required to be set to a non-zero value are defined.
+//
+// The segment register definition is defined for processor reset/real mode
+// (as when an INIT of the vCPU is requested). Should other modes (long mode,
+// etc.) be required, then the definitions can be enhanced.
+//
+
+//
+// Segment types at processor reset, See AMD APM Volume 2, Table 14-2.
+//
+#define SEV_ES_RESET_CODE_SEGMENT_TYPE  0xA
+#define SEV_ES_RESET_DATA_SEGMENT_TYPE  0x2
+
+#define SEV_ES_RESET_LDT_TYPE           0x2
+#define SEV_ES_RESET_TSS_TYPE           0x3
+
+#pragma pack (1)
+typedef union {
+    struct {
+      UINT16  Type:4;
+      UINT16  Sbit:1;
+      UINT16  Dpl:2;
+      UINT16  Present:1;
+      UINT16  Avl:1;
+      UINT16  Reserved1:1;
+      UINT16  Db:1;
+      UINT16  Granularity:1;
+    } Bits;
+    UINT16  Uint16;
+} SEV_ES_SEGMENT_REGISTER_ATTRIBUTES;
+
+typedef struct {
+  UINT16                                Selector;
+  SEV_ES_SEGMENT_REGISTER_ATTRIBUTES    Attributes;
+  UINT32                                Limit;
+  UINT64                                Base;
+} SEV_ES_SEGMENT_REGISTER;
+
+typedef struct {
+  SEV_ES_SEGMENT_REGISTER  Es;
+  SEV_ES_SEGMENT_REGISTER  Cs;
+  SEV_ES_SEGMENT_REGISTER  Ss;
+  SEV_ES_SEGMENT_REGISTER  Ds;
+  SEV_ES_SEGMENT_REGISTER  Fs;
+  SEV_ES_SEGMENT_REGISTER  Gs;
+  SEV_ES_SEGMENT_REGISTER  Gdtr;
+  SEV_ES_SEGMENT_REGISTER  Ldtr;
+  SEV_ES_SEGMENT_REGISTER  Idtr;
+  SEV_ES_SEGMENT_REGISTER  Tr;
+  UINT8                    Reserved1[42];
+  UINT8                    Vmpl;
+  UINT8                    Reserved2[5];
+  UINT64                   Efer;
+  UINT8                    Reserved3[112];
+  UINT64                   Cr4;
+  UINT8                    Reserved4[8];
+  UINT64                   Cr0;
+  UINT64                   Dr7;
+  UINT64                   Dr6;
+  UINT64                   Rflags;
+  UINT64                   Rip;
+  UINT8                    Reserved5[232];
+  UINT64                   GPat;
+  UINT8                    Reserved6[320];
+  UINT64                   SevFeatures;
+  UINT8                    Reserved7[48];
+  UINT64                   XCr0;
+  UINT8                    Reserved8[24];
+  UINT32                   Mxcsr;
+  UINT16                   X87Ftw;
+  UINT8                    Reserved9[2];
+  UINT16                   X87Fcw;
+} SEV_ES_SAVE_AREA;
+#pragma pack ()
+
 #endif