Introduction
The Platform System Interface Specification, or psi-spec, is a collection of documents for hardware and software co-design from a general perspective. It describes how microprocessors can provide an environment for booting an operating system or otherwise bare-metal applications, typically starting from intermediate, rewritable code that initializes clocks, DRAM and peripherals, commonly referred to as boot firmware or platform initialization firmware.
In the following sections, psi-spec describes principles and abstractions that apply agnostic of vendors and products.