Specifications
AMD Geode™ GeodeROM Functional Specification 11
1
Overview 32087C
1.0Overview
1.1 Scope
GeodeROM is the firmware for AMD Geode™ solutions. It is a set of components designed to initialize devices, provide
interrupt services, and emulate traditional hardware functionality. GeodeROM is targeted for platform designs using an
AMD Geode™ GX1, AMD Geode™ GX, or AMD Geode™ LX processor and companion device or a single chip processor
(e.g., SC1100, SC1200, SC1201, SC2200, SC3200). Figure 1-1 illustrates the general functionality of GeodeROM.
1.2 General Description
The functional layout depicts the operational components of the GeodeROM Power-On Self Test (POST), as well as other
services. During POST, the Geode devices are initialized along with other devices (such as the SuperI/O) and the SDRAM
is identified, configured, and optimized. This document refers to the GeodeROM System Management Mode (SMM) soft-
ware as AMD’s VSA2 (Virtual System Architecture
™
) technology. VSA2 software, including emulated hardware, is decom-
pressed and initialized. System ROMs are included to support other special functionality. There may also be adapter ROMs
present in the system or ROM binaries embedded in the GeodeROM image. These ROMs are decompressed, shadowed,
and initialized. Finally, an operating system is started. GeodeROM also contains some miscellaneous runtime support ser-
vices.
The GeodeROM image consists of POST code, initialization routines, and other features. The initialization code and vari-
ous runtime services reside in the upper 64 KB of the GeodeROM image. Features such as option ROMs, VSA2 technol-
ogy, or a splash screen bitmap are compressed. The compressed binary images are pre-padded to 192 KB. The
initialization and support code is concatenated to the 192 KB image.
Figure 1-1. GeodeROM Functionality
256 KB
GeodeROM
Core Features
Initialization Routines
192 KB
Variable
Compressed Images:
- VSA2 Software and VSMs
0
Padded Free Space
POST
Execution
Initialize AMD Geode™
Solutions
Decompress and
Initialize VSA2 Software
Decompress and
Initialize System ROM
(HDD, FDD, KB Support)
Flow
Start
Operating System
Runtime
Services
Miscellaneous
GeodeROM Functional Layout
GeodeROM Flash Image
- Splash Bitmap
- System ROMs