System and method for firmware integrity verification using multiple keys and OTP memory

摘要

A processing system is disclosed along with a concept for controlling access of a processing unit of the processing system to firmware code. It is proposed to identify a valid key stored in a first region of memory based on validation data of a second region of the memory, the validation data indicating whether a key is valid or not. The firmware code is processed in accordance with a predetermined verification algorithm to compute a verification value for the firmware code. The verification value and the valid key are analysed to determine if the firmware code is trusted. Access of the processing unit to the firmware code is controlled based on whether the firmware code is determined to be trusted or not.