1 files changed, 60 insertions, 0 deletions
diff --git a/roms/edk2/MdePkg/Library/BaseLib/X64/CpuIdEx.nasm b/roms/edk2/MdePkg/Library/BaseLib/X64/CpuIdEx.nasm
new file mode 100644
index 000000000..fd5caa328
--- /dev/null
+++ b/roms/edk2/MdePkg/Library/BaseLib/X64/CpuIdEx.nasm
@@ -0,0 +1,60 @@
+;------------------------------------------------------------------------------
+;
+; Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
+; SPDX-License-Identifier: BSD-2-Clause-Patent
+;
+; Module Name:
+;
+;   CpuIdEx.Asm
+;
+; Abstract:
+;
+;   AsmCpuidEx function
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+    DEFAULT REL
+    SECTION .text
+
+;------------------------------------------------------------------------------
+;  UINT32
+;  EFIAPI
+;  AsmCpuidEx (
+;    IN   UINT32  RegisterInEax,
+;    IN   UINT32  RegisterInEcx,
+;    OUT  UINT32  *RegisterOutEax  OPTIONAL,
+;    OUT  UINT32  *RegisterOutEbx  OPTIONAL,
+;    OUT  UINT32  *RegisterOutEcx  OPTIONAL,
+;    OUT  UINT32  *RegisterOutEdx  OPTIONAL
+;    )
+;------------------------------------------------------------------------------
+global ASM_PFX(AsmCpuidEx)
+ASM_PFX(AsmCpuidEx):
+    push    rbx
+    mov     eax, ecx
+    mov     ecx, edx
+    push    rax                         ; save Index on stack
+    cpuid
+    mov     r10, [rsp + 0x38]
+    test    r10, r10
+    jz      .0
+    mov     [r10], ecx
+.0:
+    mov     rcx, r8
+    jrcxz   .1
+    mov     [rcx], eax
+.1:
+    mov     rcx, r9
+    jrcxz   .2
+    mov     [rcx], ebx
+.2:
+    mov     rcx, [rsp + 0x40]
+    jrcxz   .3
+    mov     [rcx], edx
+.3:
+    pop     rax                         ; restore Index to rax as return value
+    pop     rbx
+    ret
+