The wiki is being retired!
Documentation is now handled by the same processes we use for code: Add something to the Documentation/ directory in the coreboot repo, and it will be rendered to https://doc.coreboot.org/. Contributions welcome!
TianoCore is an open source implementation of UEFI, the Unified Extensible Firmware Interface. UEFI (formerly EFI) is intended to replace the traditional PC BIOS. TianoCore as in implementation cannot do that, as it lacks the code to do hardware initalization. Since hardware initialization is exactly what coreboot does, the combination of coreboot + TianoCore is the most straightforward option to provide a complete, opensource UEFI environment.