When we switch on a computer, it goes through a series of steps before it is able to load the operating system. In this post we will see how a typical x86 processor boots. This is a very complex and involved process. We will only present a basic overall structure. Also what path is actually taken by the processor to reach a state where it can load an OS, is dependent on boot firmware. We will follow example of coreboot, an open source boot firmware.[…]
https://binarydebt.wordpress.com/2018/10/06/how-does-an-x86-processor-boot/
Firmware Security 