https://blog.wongcw.com/2021/07/28/%e5%a4%96%e5%aa%92%e7%a8%b1%e4%b8%80%e5%8a%a08t-9r%e8%a8%98%e6%86%b6%e9%ab%94%e6%82%84%e7%84%b6%e5%be%9elpddr4x%e5%8d%87%e7%b4%9a%e5%88%b0lpddr5/