diff --git a/usr/src/sp1/head/amd64/cpudef.h b/usr/src/sp1/head/amd64/cpudef.h
new file mode 100644
index 0000000..b9aca80
--- /dev/null
+++ b/usr/src/sp1/head/amd64/cpudef.h
@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2026, Mirocom Laboratories
+ * All rights reserved.
+ *
+ * The following sources are CONFIDENTIAL and PROPRIETARY
+ * property of Mirocom Laboratories. Unauthorized copying,
+ * use, distribution or modification of this file, in whole
+ * and in part, is strictly prohibited without the prior written
+ * consent from Mirocom Laboratories.
+ */
+
+#ifndef _MACHINE_CPUDEF_H_
+#define _MACHINE_CPUDEF_H_ 1
+
+#include <sys/cdefs.h>
+
+#define md_cpu_halt()  \
+    __asmv("hlt" ::: "memory")
+
+#define md_cpu_wait() \
+    __asmv("pause" ::: "memory")
+
+#define md_cpu_intoff() \
+    __asmv("cli" ::: "memory")
+
+#define md_cpu_inton()  \
+    __asmv("sti" ::: "memory")
+
+#endif  /* !_MACHINE_CPUDEF_H_ */
diff --git a/usr/src/sp1/head/mu/cpu.h b/usr/src/sp1/head/mu/cpu.h
index dc9a0f7..19b57ff 100644
--- a/usr/src/sp1/head/mu/cpu.h
+++ b/usr/src/sp1/head/mu/cpu.h
@@ -14,6 +14,13 @@
 
 #include <sys/types.h>
 #include <machine/mcb.h>    /* shared */
+#include <machine/cpudef.h> /* shared */
+
+/* cpudef.h glue */
+#define mu_cpu_halt md_cpu_halt             /* Halt current core */
+#define mu_cpu_wait md_cpu_wait             /* Spinwait hint */
+#define mu_cpu_intoff md_cpu_intoff         /* Disable interrupts */
+#define mu_cpu_inton md_cpu_inton           /* Enable interrupts */
 
 /*
  * MI processor specific information