Intel Extensible Firmware Interface - Manual (Page 5)

Version 1.10 12/01/02 v
Contents
1 Introduction
1.1 EFI Driver Model Extensions............................................................................... 1-2
1.2 Overview............................................................................................................. 1-3
1.3 Goals .................................................................................................................. 1-6
1.4 Target Audience.................................................................................................. 1-8
1.5 EFI Design Overview .......................................................................................... 1-8
1.6 EFI Driver Model ................................................................................................. 1-9
1.6.1 EFI Driver Model Goals ............................................................................ 1-10
1.6.2 Legacy Option ROM Issues...................................................................... 1-11
1.7 Migration Requirements .................................................................................... 1-11
1.7.1 Legacy Operating System Support........................................................... 1-11
1.7.2 Supporting the EFI Specification on a Legacy Platform ............................ 1-11
1.8 Conventions Used in This Document ................................................................ 1-12
1.8.1 Data Structure Descriptions...................................................................... 1-12
1.8.2 Protocol Descriptions ............................................................................... 1-12
1.8.3 Procedure Descriptions ............................................................................ 1-13
1.8.4 Instruction Descriptions ............................................................................ 1-13
1.8.5 Pseudo-Code Conventions....................................................................... 1-14
1.8.6 Typographic Conventions......................................................................... 1-14
2 Overview
2.1 Boot Manager ..................................................................................................... 2-2
2.1.1 EFI Images................................................................................................. 2-2
2.1.2 EFI Applications ......................................................................................... 2-3
2.1.3 EFI OS Loaders ......................................................................................... 2-4
2.1.4 EFI Drivers ................................................................................................. 2-4
2.2 Firmware Core .................................................................................................... 2-5
2.2.1 EFI Services............................................................................................... 2-5
2.2.2 Runtime Services ....................................................................................... 2-6
2.3 Calling Conventions ............................................................................................ 2-7
2.3.1 Data Types................................................................................................. 2-7
2.3.2 IA-32 Platforms .......................................................................................... 2-9
2.3.2.1 Handoff State .................................................................................. 2-10
2.3.3 Itanium ® -Based Platforms ........................................................................ 2-11
2.3.3.1 Handoff State .................................................................................. 2-12
2.4 Protocols........................................................................................................... 2-12
2.5 EFI Driver Model ............................................................................................... 2-15
2.5.1 Legacy Option ROM Issues...................................................................... 2-17
2.5.1.1 IA-32 16-Bit Real Mode Binaries...................................................... 2-17
2.5.1.2 Fixed Resources for Working with Option ROMs............................. 2-18
2.5.1.3 Matching Option ROMs to their Devices .......................................... 2-18
2.5.1.4 Ties to PC-AT System Design ......................................................... 2-19
2.5.1.5 Ambiguities in Specification and Workarounds
Born of Experience .......................................................................... 2-19