一:概述
平台介绍:RK3399,U-Boot 2017.09(next-dev版本),Kernel 4.4.194
Uboot在启动阶段会根据cmd,misc以及key键入情况设置不同的Boot Mode,从而引导不同Boot。
/*
* There are three ways to get reboot-mode:
*
* No1. Android BCB which is defined in misc.img (0KB or 16KB offset)
* No2. CONFIG_ROCKCHIP_BOOT_MODE_REG that supports "reboot xxx" commands
* No3. Env variable "reboot_mode" which is added by U-Boot
*
* Recovery mode from:
* - Android BCB in misc.img
* - "reboot recovery" command
* - recovery key pressed without usb attach
*/
常见boot模式:None,watchdog,panic,rec