AMD Platform Security Processor

The AMD Platform Security Processor (PSP), officially known as AMD Secure Technology, is a trusted execution environment subsystem incorporated since about 2013 into AMD microprocessors. According to an AMD developer's guide, the subsystem is "responsible for creating, monitoring and maintaining the security environment" and "its functions include managing the boot process, initializing various security related mechanisms, and monitoring the system for any type of activity or events and implementing an appropriate response".

Source: Wikipedia — AMD Platform Security Processor (CC BY-SA 4.0)