fdt_get_mem_rsv
if (fdt_get_mem_rsv(fdt, i, &base, &size) < 0)
res = fdt_get_mem_rsv(initial_boot_params, n, &base, &size);
ret = fdt_get_mem_rsv(fdt, i, &rsv_start, &rsv_size);
int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);