UEFI : THE SUPER BIOS (Faster, Safer and more Efficient)

The Unified Extensible Firmware Interface (UEFI) specification defines a new model for the interface between operating systems and platform firmware. The interface consists of data tables that contain platform-related information, plus boot and runtime service calls that are available to the operating system and its loader. Together, these provide a standard, modern environment for booting an operating system and running pre-boot applications.

The BIOS used by PC/AT compatible systems is based on the x86, 16-bit, real-mode architecture. However UEFI is not specific to any processor architecture, so it can perform the same function as BIOS while evolving with new technologies.  The current UEFI specification allows operating systems to boot using modern modes and calling conventions.                                          

                                                                             

  

This is what the UEFI screen looks like(simply amazing!!)

UEFI is the successor to EFI.  Intel contributed EFI 1.10 (the final version of EFI) as the starting point

for UEFI specifications.  Enhancements are managed by the UEFI Forum.  Intel retains copyright to the EFI 1.10 specification. UEFI works to standardize two primary functions of the PC Basic Input/Output System (BIOS): firmware-to-OS interface and platform initialization. The UEFI Specification Working Group (USWG) creates the UEFI specification, describing a firmware-to-OS interface analogous to BIOS software interrupts and the BIOS data area (BDA). The Platform Initialization Working Group (PIWG) specifications are intended to promote interoperability between firmware components provided by different entities, such as silicon vendors and firmware vendors.

UEFI was designed to bring modularity to system firmware by implementing a driver-based approach to platform initialization. Hardware and device chipsets will have a UEFI driver that allows the system firmware to initialize them through a standard API rather than having to program them directly.   

     

UEFI Architecture

UEFI also establishes its own pre-OS environment, including APIs and services that can be used to create applications for a variety of purposes, including configuration. This is known as the UEFI Shell.

 

         

UEFI enabled Motherboard

The UEFI boot process in comparison to BIOS boot process

Both the old BIOS and its successor UEFI provide interface between components of the motherboard and the operating systems. So as to speed up the boot time UEFI provides some clever functions as illustrated.