EDK - A modern, feature-rich, cross-platform firmware development environment for the UEFI and PI specifications

EDK II is a modern, feature-rich, cross-platform firmware development environment for the UEFI and PI specifications. You can refer to Getting Started with EDK II - steps for downloading EDK II and compiling projects under various OS/compiler environments. There are multiple hardware platforms using EDK II open source UEFI firmware, including MinnowBoard Max/Turbot, Aaeon UpSquared, and Intel® Galileo Gen 2. This allows you to experiment and develop UEFI features on real hardware.

TianoCore, the community supporting an open source implementation of Unified Extensible Firmware Interface (UEFI).