generic_bs_subregion
generic_bs_subregion(bus_space_tag_t t, bus_space_handle_t bsh, bus_size_t offset,
generic_bs_subregion(void *t, bus_space_handle_t bsh, bus_size_t offset,
generic_bs_subregion(void *t, bus_space_handle_t bsh, bus_size_t offset,