diff --git a/arch/x86_64/src/intel64/intel64.h b/arch/x86_64/src/intel64/intel64.h
index b73a0ab890b..40220d4c78d 100644
--- a/arch/x86_64/src/intel64/intel64.h
+++ b/arch/x86_64/src/intel64/intel64.h
@@ -68,19 +68,6 @@ extern "C"
  * Public Function Prototypes
  ****************************************************************************/
 
-/****************************************************************************
- * Name: intel64_lowsetup
- *
- * Description:
- *   Called at the very beginning of _nxstart.
- *   Performs low level initializationincluding setup of the console UART.
- *   This UART done early so that the serial console is available for
- *   debugging very early in the boot sequence.
- *
- ****************************************************************************/
-
-void intel64_lowsetup(void);
-
 /****************************************************************************
  * Name: vector_*
  *
diff --git a/arch/x86_64/src/intel64/intel64_lowsetup.h b/arch/x86_64/src/intel64/intel64_lowsetup.h
new file mode 100644
index 00000000000..a50602a74b1
--- /dev/null
+++ b/arch/x86_64/src/intel64/intel64_lowsetup.h
@@ -0,0 +1,64 @@
+/****************************************************************************
+ * arch/x86_64/src/intel64/intel64_lowsetup.h
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __ARCH_X86_64_SRC_INTEL64_INTEL64_LOWSETUP_H
+#define __ARCH_X86_64_SRC_INTEL64_INTEL64_LOWSETUP_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#ifndef __ASSEMBLY__
+
+#undef EXTERN
+#if defined(__cplusplus)
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: intel64_lowsetup
+ *
+ * Description:
+ *   Called at the very beginning of _nxstart or up_ap_boot.
+ *   Performs low level initializationincluding setup of the console UART.
+ *   This UART done early so that the serial console is available for
+ *   debugging very early in the boot sequence.
+ *
+ ****************************************************************************/
+
+void intel64_lowsetup(void);
+
+#undef EXTERN
+#if defined(__cplusplus)
+}
+#endif
+
+#endif /* __ASSEMBLY__ */
+#endif /* __ARCH_X86_64_SRC_INTEL64_INTEL64_LOWSETUP_H */
diff --git a/arch/x86_64/src/intel64/intel64_start.c b/arch/x86_64/src/intel64/intel64_start.c
index 38a4282a04e..d9e50a165c3 100644
--- a/arch/x86_64/src/intel64/intel64_start.c
+++ b/arch/x86_64/src/intel64/intel64_start.c
@@ -30,7 +30,8 @@
 #include <arch/multiboot2.h>
 
 #include "x86_64_internal.h"
-#include "intel64.h"
+
+#include "intel64_lowsetup.h"
 
 /****************************************************************************
  * Public Data