1. Boot stage BL1,BL2,BL31,BL32,BL33 2. Exception level EL3, EL1S, EL2 3. 那么放在表格里比较一下咯 Boot stage Exception level Description BL1 EL3 Boot ROM firmware (这一段程序由硬件完成，无法修改) Note:BL1 is embe
1. Boot stage
BL1,BL2,BL31,BL32,BL33
2. Exception level
EL3, EL1S, EL2
3. 那么放在表格里比较一下咯
Boot stage Exception level Description BL1 EL3 Boot ROM firmware (这一段程序由硬件完成，无法修改) Note: BL1 is embedded in hardware (Boot ROM + PBL commands) BL2 EL3
Platform initialization firmware(平台初始化固件)
BL31 EL3 Resident runtime firmware BL32 EL1S [Optional] Trusted operating system. For example, OP-TEE BL33 EL2 Normal world bootloader. For example, U-Boot, UEFI