[kryptiskt]

Below UEFI is the BIOS, or the firmware formerly known as the BIOS. There is a project to make an open source firmware for PCs: https://www.coreboot.org. It works on a selection of newish motherboards.

You can't really start completely from scratch in an understandable way on Intel platforms, and it's iffy on ARM. Because setting up the DRAM requires some insane magic, where it doesn't really help if you can see the source.

[izacus]

> Below UEFI is the BIOS, or the firmware formerly known as the BIOS. There is a project to make an open source firmware for PCs: https://www.coreboot.org. It works on a selection of newish motherboards.

This simply isn't true - while UEFI firmwares do offer BIOS emulation, there's no "BIOS" underneath them on most modern boards.

[XMPPwocky]

They might mean the "meta-bootloader" which brings up all those UEFI capsules- afaik Intel's boot ROM doesn't, for example, parse PE headers.

[wolfgke]

> Below UEFI is the BIOS, or the firmware formerly known as the BIOS.

Source?

As far as I am aware, UEFI is a replacement for BIOS.

[Rusky]

I believe they're using BIOS in a more general sense. You're right that UEFI replaces the old BIOS APIs that bootloaders used, but there's still firmware (e.g. coreboot) below or part of its newer APIs.