Qualcomm Snapdragon processors support secure boot which ensures only authenticated software runs on the device. By configuring the processor for secure boot, unauthorized or modified code is prevented from being run. The authenticity of the image is verified by use digital signatures and certificate chain.

Secure boot process overview

On Qualcomm processors the first piece of software that runs is called Primary BootLoader (PBL) and it resides in immutable read-only-memory (ROM) of the processor. By configuring the processor for secure boot, PBL can verify the authenticity of the Secondary BootLoader (SBL) before executing it.