diff --git a/hw/spapr.h b/hw/spapr.h
index efe7f5758f..971a50ab02 100644
--- a/hw/spapr.h
+++ b/hw/spapr.h
@@ -320,7 +320,7 @@ static inline void rtas_st(target_ulong phys, int n, uint32_t val)
 typedef void (*spapr_rtas_fn)(sPAPREnvironment *spapr, uint32_t token,
                               uint32_t nargs, target_ulong args,
                               uint32_t nret, target_ulong rets);
-void spapr_rtas_register(const char *name, spapr_rtas_fn fn);
+int spapr_rtas_register(const char *name, spapr_rtas_fn fn);
 target_ulong spapr_rtas_call(sPAPREnvironment *spapr,
                              uint32_t token, uint32_t nargs, target_ulong args,
                              uint32_t nret, target_ulong rets);
diff --git a/hw/spapr_rtas.c b/hw/spapr_rtas.c
index 6d5c48a740..45294e8305 100644
--- a/hw/spapr_rtas.c
+++ b/hw/spapr_rtas.c
@@ -242,7 +242,7 @@ target_ulong spapr_rtas_call(sPAPREnvironment *spapr,
     return H_PARAMETER;
 }
 
-void spapr_rtas_register(const char *name, spapr_rtas_fn fn)
+int spapr_rtas_register(const char *name, spapr_rtas_fn fn)
 {
     int i;
 
@@ -258,7 +258,7 @@ void spapr_rtas_register(const char *name, spapr_rtas_fn fn)
     rtas_next->name = name;
     rtas_next->fn = fn;
 
-    rtas_next++;
+    return (rtas_next++ - rtas_table) + TOKEN_BASE;
 }
 
 int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,