linux-kernel - android下bootloader后进入recovery流程，属于安卓架构的哪一层面？

Question

最近在了解安卓下进入recovery后的整体流程，包括factory reset和OTA升级的具体实现方法（源码），其中包括little kernel，recovery.cpp，init.rc，install.cpp，screen_ui.cpp等等。
想知道这个流程或者说这块内容属于安卓架构里面的哪一层？就是所谓的什么内核层，library层，应用层这种，还是说不属于里面的任何一层？
用到了OpenGrok，但奇怪的是我电脑没有配置过opengrok，为什么在浏览器里输入一个IP地址就直接可以使用并查阅代码了，是公司的服务器那边已经配置好了还是？

Answer 1

The bootloader recovery process belongs to the embedded hardware startup program and does not belong to any layer of the Android architecture we often say. The bottom layer of the Android system architecture we often say is the kernel layer. Responsible for hardware power-on and startup, etc., and then starting the Linux kernel. Bootloader recovery is similar to the PC motherboard BIOS program, but there is a big difference. BIOS has "standards", and embedded hardware configurations are ever-changing. The bootloader recovery of each embedded device may be different, just like the usual mention of Android To flash a mobile phone, you generally need to find the corresponding recovery first to ensure that the flashing proceeds normally.
I have never used OpenGrok, so I don’t know the cause of the problem you encountered.

Answer 2

Let me answer the question about open grok. This code warehouse must be built by your company yourself, so that you can easily view the code in your project.

Answer 3

Bootloader is part of the Linux startup process. It is recommended to read embedded books. I remember that the more famous open source version in this area is u-boot