Abstract: The extensible firmware interface(EFI) specification provides a standard environment for booting an OS. And NUWA system is a graphics user interface specialized for EFI environment with multi-layer design model. Graphics abstract layer(GAL) and input abstract layer (IAL) are the two abstract layers in NUWA system independent of any hardware. And the codes to implement these two layers initiate the “graphics engine” of NUWA, like the drivers in OS. This paper introduces the implementation of GAL using the EFI drive model.

Key words: extensible firmware interface(EFI), graphics abstract layer(GAL), input abstract layer (IAL), driver

摘要： 可扩展固件接口(EFI)规范为启动操作系统前的程序提供了一个标准环境。NUWA系统是一个专门针对EFI环境开发的图形用户界面。该系统采用分层设计思想，其中的图形抽象层(GAL)与输入抽象层(IAL)定义了一组不依赖于任何特殊硬件的抽象接口，而用于实现这一抽象接口的底层代码形成了NUWA系统的“图形引擎”，类似于操作系统中的驱动程序。该文介绍了GAL与IAL的设计以及在EFI环境下GAL驱动程序的实现。

关键词: 可扩展固件接口, GAL, IAL, 驱动程序

CLC Number: 

• TP311