1 files changed, 58 insertions, 0 deletions
diff --git a/OvmfPkg/IntelTdx/Sec/X64/IntelTdxAPs.nasm b/OvmfPkg/IntelTdx/Sec/X64/IntelTdxAPs.nasm
new file mode 100644
index 0000000000..034ac0ee94
--- /dev/null
+++ b/OvmfPkg/IntelTdx/Sec/X64/IntelTdxAPs.nasm
@@ -0,0 +1,58 @@
+;------------------------------------------------------------------------------
+; @file
+; Intel TDX APs
+;
+; Copyright (c) 2021 - 2022, Intel Corporation. All rights reserved.<BR>
+; SPDX-License-Identifier: BSD-2-Clause-Patent
+;
+;------------------------------------------------------------------------------
+
+%include "TdxCommondefs.inc"
+
+    ;
+    ; Note: BSP never gets here. APs will be unblocked by DXE
+    ;
+    ; R8  [31:0]  NUM_VCPUS
+    ;     [63:32] MAX_VCPUS
+    ; R9  [31:0]  VCPU_INDEX
+    ;
+ParkAp:
+
+do_wait_loop:
+    ;
+    ; register itself in [rsp + CpuArrivalOffset]
+    ;
+    mov       rax, 1
+    lock xadd dword [rsp + CpuArrivalOffset], eax
+    inc       eax
+
+.check_arrival_cnt:
+    cmp       eax, r8d
+    je        .check_command
+    mov       eax, dword[rsp + CpuArrivalOffset]
+    jmp       .check_arrival_cnt
+
+.check_command:
+    mov     eax, dword[rsp + CommandOffset]
+    cmp     eax, MpProtectedModeWakeupCommandNoop
+    je      .check_command
+
+    cmp     eax, MpProtectedModeWakeupCommandWakeup
+    je      .do_wakeup
+
+    ; Don't support this command, so ignore
+    jmp     .check_command
+
+.do_wakeup:
+    ;
+    ; BSP sets these variables before unblocking APs
+    ;   RAX:  WakeupVectorOffset
+    ;   RBX:  Relocated mailbox address
+    ;   RBP:  vCpuId
+    ;
+    mov     rax, 0
+    mov     eax, dword[rsp + WakeupVectorOffset]
+    mov     rbx, [rsp + WakeupArgsRelocatedMailBox]
+    nop
+    jmp     rax
+    jmp     $