1 files changed, 37 insertions, 0 deletions
diff --git a/roms/edk2/MdePkg/Library/BaseLib/X64/WriteDr4.nasm b/roms/edk2/MdePkg/Library/BaseLib/X64/WriteDr4.nasm
new file mode 100644
index 000000000..c4b12c9e9
--- /dev/null
+++ b/roms/edk2/MdePkg/Library/BaseLib/X64/WriteDr4.nasm
@@ -0,0 +1,37 @@
+;------------------------------------------------------------------------------
+;
+; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
+; SPDX-License-Identifier: BSD-2-Clause-Patent
+;
+; Module Name:
+;
+;   WriteDr4.Asm
+;
+; Abstract:
+;
+;   AsmWriteDr4 function
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+    DEFAULT REL
+    SECTION .text
+
+;------------------------------------------------------------------------------
+; UINTN
+; EFIAPI
+; AsmWriteDr4 (
+;   IN UINTN Value
+;   );
+;------------------------------------------------------------------------------
+global ASM_PFX(AsmWriteDr4)
+ASM_PFX(AsmWriteDr4):
+    ;
+    ; There's no obvious reason to access this register, since it's aliased to
+    ; DR6 when DE=0 or an exception generated when DE=1
+    ;
+    DB      0xf, 0x23, 0xe1
+    mov     rax, rcx
+    ret
+