diff --git a/src/amd/common/ac_msgpack.c b/src/amd/common/ac_msgpack.c
index 0d28a413fe2..60b820fc6a0 100644
--- a/src/amd/common/ac_msgpack.c
+++ b/src/amd/common/ac_msgpack.c
@@ -123,7 +123,7 @@ void ac_msgpack_add_fixarray_op(struct ac_msgpack *msgpack, uint32_t n)
    }
 }
 
-void ac_msgpack_add_fixstr(struct ac_msgpack *msgpack, char *str)
+void ac_msgpack_add_fixstr(struct ac_msgpack *msgpack, const char *str)
 {
    uint32_t n;
 
diff --git a/src/amd/common/ac_msgpack.h b/src/amd/common/ac_msgpack.h
index 29b4ff303fd..3b3c29d2b56 100644
--- a/src/amd/common/ac_msgpack.h
+++ b/src/amd/common/ac_msgpack.h
@@ -19,7 +19,7 @@ int ac_msgpack_resize_if_required(struct ac_msgpack *msgpack,
                                   uint32_t data_size);
 void ac_msgpack_add_fixmap_op(struct ac_msgpack *msgpack, uint32_t n);
 void ac_msgpack_add_fixarray_op(struct ac_msgpack *msgpack, uint32_t n);
-void ac_msgpack_add_fixstr(struct ac_msgpack *msgpack, char *str);
+void ac_msgpack_add_fixstr(struct ac_msgpack *msgpack, const char *str);
 void ac_msgpack_add_uint(struct ac_msgpack *msgpack, uint64_t val);
 void ac_msgpack_add_int(struct ac_msgpack *msgpack, int64_t val);