diff --git a/services/std_svc/spm/common/include/spm_common.h b/services/std_svc/spm/common/include/spm_common.h
new file mode 100644
index 0000000..68805fc
--- /dev/null
+++ b/services/std_svc/spm/common/include/spm_common.h
@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2017-2022, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef SPM_COMMON_H
+#define SPM_COMMON_H
+
+#include <context.h>
+
+/*******************************************************************************
+ * Constants that allow assembler code to preserve callee-saved registers of the
+ * C runtime context while performing a security state switch.
+ ******************************************************************************/
+#define SP_C_RT_CTX_X19		0x0
+#define SP_C_RT_CTX_X20		0x8
+#define SP_C_RT_CTX_X21		0x10
+#define SP_C_RT_CTX_X22		0x18
+#define SP_C_RT_CTX_X23		0x20
+#define SP_C_RT_CTX_X24		0x28
+#define SP_C_RT_CTX_X25		0x30
+#define SP_C_RT_CTX_X26		0x38
+#define SP_C_RT_CTX_X27		0x40
+#define SP_C_RT_CTX_X28		0x48
+#define SP_C_RT_CTX_X29		0x50
+#define SP_C_RT_CTX_X30		0x58
+
+#define SP_C_RT_CTX_SIZE	0x60
+#define SP_C_RT_CTX_ENTRIES	(SP_C_RT_CTX_SIZE >> DWORD_SHIFT)
+
+#ifndef __ASSEMBLER__
+
+#include <stdint.h>
+
+/* Assembly helpers */
+uint64_t spm_secure_partition_enter(uint64_t *c_rt_ctx);
+void __dead2 spm_secure_partition_exit(uint64_t c_rt_ctx, uint64_t ret);
+
+#endif /* __ASSEMBLER__ */
+
+#endif /* SPM_COMMON_H */