diff --git a/include/boot/sigp.h b/include/boot/sigp.h
new file mode 100644
index 00000000..c3e7d482
--- /dev/null
+++ b/include/boot/sigp.h
@@ -0,0 +1,55 @@
+/*
+ * SIGP related definitions and functions.
+ *
+ * Copyright IBM Corp. 2020
+ *
+ * s390-tools is free software; you can redistribute it and/or modify
+ * it under the terms of the MIT license. See LICENSE for details.
+ */
+
+#ifndef S390_SIGP_H
+#define S390_SIGP_H
+
+/* Signal Processor Order Codes */
+#define SIGP_STOP_AND_STORE_STATUS	9
+#define SIGP_SET_MULTI_THREADING	22
+#define SIGP_STORE_ASTATUS_AT_ADDRESS	23
+
+/* Signal Processor Condition Codes */
+#define SIGP_CC_ORDER_CODE_ACCEPTED	0
+#define SIGP_CC_BUSY			2
+
+
+#ifndef __ASSEMBLER__
+
+#include <stdint.h>
+
+static inline int sigp(uint16_t addr, uint8_t order, uint32_t parm,
+		       uint32_t *status)
+{
+	register unsigned int reg1 asm ("1") = parm;
+	int cc;
+
+	asm volatile(
+		"	sigp	%1,%2,0(%3)\n"
+		"	ipm	%0\n"
+		"	srl	%0,28\n"
+		: "=d" (cc), "+d" (reg1) : "d" (addr), "a" (order) : "cc");
+	if (status && cc == 1)
+		*status = reg1;
+	return cc;
+}
+
+static inline int sigp_busy(uint16_t addr, uint8_t order, uint32_t parm,
+			    uint32_t *status)
+{
+	int cc;
+
+	do {
+		cc = sigp(addr, order, parm, status);
+	} while (cc == SIGP_CC_BUSY);
+	return cc;
+}
+
+#endif /* __ASSEMBLER__ */
+#endif /* S390_SIGP_H */
diff --git a/zipl/boot/s390.h b/zipl/boot/s390.h
index 6de5766c..ff0a43fc 100644
--- a/zipl/boot/s390.h
+++ b/zipl/boot/s390.h
@@ -13,6 +13,7 @@
 
 #include "lib/zt_common.h"
 #include "libc.h"
+#include "boot/sigp.h"
 
 #define __pa32(x) ((uint32_t)(unsigned long)(x))
 #define __pa(x) ((unsigned long)(x))
@@ -294,43 +295,6 @@ static inline int diag308(unsigned long subcode, void *addr)
 	return _rc;
 }
 
-/*
- * Signal Processor
- */
-#define SIGP_STOP_AND_STORE_STATUS	9
-#define SIGP_SET_MULTI_THREADING	22
-#define SIGP_STORE_ASTATUS_AT_ADDRESS	23
-
-#define SIGP_CC_ORDER_CODE_ACCEPTED	0
-#define SIGP_CC_BUSY			2
-
-static inline int sigp(uint16_t addr, uint8_t order, uint32_t parm,
-		       uint32_t *status)
-{
-	register unsigned int reg1 asm ("1") = parm;
-	int cc;
-
-	asm volatile(
-		"	sigp	%1,%2,0(%3)\n"
-		"	ipm	%0\n"
-		"	srl	%0,28\n"
-		: "=d" (cc), "+d" (reg1) : "d" (addr), "a" (order) : "cc");
-	if (status && cc == 1)
-		*status = reg1;
-	return cc;
-}
-
-static inline int sigp_busy(uint16_t addr, uint8_t order, uint32_t parm,
-			    uint32_t *status)
-{
-	int cc;
-
-	do {
-		cc = sigp(addr, order, parm, status);
-	} while (cc == SIGP_CC_BUSY);
-	return cc;
-}
-
 /*
  * Store CPU address
  */