Microsoft releases Mu open-source UEFI firmware

Microsoft's Devices Team has announced the release of Project Mu, an effort to create an open-source version of the Unified Extensible Firmware Interface (UEFI) powering the company's Surface convertibles and Hyper-V hypervisor.

IBM's gift to the world of computing was its BIOS, a Basic Input/Output System which could sit between the software and the hardware. With an IBM PC, developers would no longer have to tailor their software for a specific hardware device: Instead, calls could be made to the BIOS which handled the hardware side automatically. When rival companies, including Compaq, cloned the IBM BIOS - either illegally, using IBM's publicly-released documentation, or through clean-room duplication which numerous lawsuits would prove legal - it launched an era of open systems whereby software could be written once and run on any 'IBM compatible' on the market.

In the years since IBM released its original BIOS, though, computing has changed, and the BIOS has changed with it: The Universal Extensible Firmware Interface (UEFI) is the modern replacement for the BIOS, and at the heart of modern PCs - including those from Microsoft, which has released an open-source UEFI implementation for its products under the codename Project Mu.

'The Microsoft Devices Team is excited to announce Project Mu, the open-source release of the Unified Extensible Firmware Interface (UEFI) core leveraged by Microsoft products including both Surface and the latest releases of Hyper-V,' the company explains in its release announcement. 'UEFI is system software that initialises hardware during the boot process and provides services for the operating system to load. Project Mu contributes numerous UEFI features targeted at modern Windows based PCs. It also demonstrates a code structure and development process for efficiently building scalable and serviceable firmware. These enhancements allow Project Mu devices to support Firmware as a Service (FaaS). Similar to Windows as a Service, Firmware as a Service optimises UEFI and other system firmware for timely quality patches that keep firmware up to date and enables efficient development of post-launch features.'

Designed with touch-controlled devices in mind - an on-screen keyboard means that settings can be adjusted and data entered without the need for an external keyboard - Project Mu is built around the existing TianoCore EDK II UEFI firmware developed by Intel, Apple, Arm, Linaro, and Red Hat. Microsoft has released its version under a BSD two-clause licence, which permits redistribution in modified or unmodified form for any purpose, including commercially, providing its copyright notice - which, oddly, does not mention any of the original EDK II developers - is included.

More information on Project Mu, though which Microsoft is hoping to foster a more collaborative development environment for UEFI firmware, is available on the official project page, along with its source code.