My guide to award BIOS reverse engineering

[Gonzalez]

Author: Pinczakko

Perhaps this article will be of use to some that may want it . Here's the link

A snippet of the contents :

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Table of Contents

* 1. Foreword

* 2. Prerequisite

o 2.1. PCI BUS

o 2.2. ISA BUS

* 3. Some Hardware Peculiarities

o 3.1. BIOS Chip Addressing

o 3.2. Obscure Hardware Port

o 3.3. "Relocatable" Hardware Port

o 3.4. Expansion ROM Handling

* 4. Some Software Peculiarities

o 4.1. Call Instruction Peculiarity

o 4.2. Retn Instruction Peculiarity

* 5. Our Tools of Trade

* 6. Award BIOS File Structure

o 6.1. The Compressed Components

o 6.2. The Pure Binary Components

o 6.3. The Memory Map In The Real System (Mainboard)

* 7. Disassembling the BIOS

o 7.1. Bootblock

+ 7.1.1 "Virtual Shutdown" routine

+ 7.1.2 Chipset_Reg_Early_Init routine

+ 7.1.3 Init_Interrupt_n_PwrMgmt routine

+ 7.1.4 Call To "Early Silicon Support" Routine

+ 7.1.5 Bootblock Is Copied And Executed In RAM

+ 7.1.6 Call to bios decompression routine and the jump into decompressed system bios

o 7.2. System BIOS a.k.a Original.tmp

+ 7.2.1. Entry point from "Bootblock in RAM"

+ 7.2.2. The awardext.rom and Extension BIOS Components (lower 128KB bios-code) Relocation Routine

+ 7.2.3. Call to the POST routine a.k.a "POST jump table execution"

+ 7.2.4. The "segment vector" Routines

+ 7.2.5. "chksum_ROM" Procedure

+ 7.2.6. Original.tmp decompression routine for the "Extension_BIOS components"

* 8. Closing

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