AMD CS5535 manual Miscellaneous Initializations, Initialize Graphics Subsystem, Monochrome Support

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Initialization

32430C

4.5Miscellaneous Initializations

In addition to the previous processor initializations, the graphics card(s) must also be initialized.

4.5.1Initialize Graphics Subsystem

There are two different modes: CRT and TFT. Graphics initialization needs to identify which kind of support is required by reading an MSR in the Video Processor.

Entry Conditions:

4 GB descriptor in FS core register.

GeodeLink descriptors initialized.

VSA initialized.

First MB of DRAM functional.

Interrupts enabled.

DMA initialized.

PCI bus functional.

Procedure:

IF <PCI graphics card exists> THEN

Jump to PCI graphics BIOS for initialization.

ELSEIF <ISA graphics card exists> THEN

Jump to ISA graphics BIOS for initialization.

ELSE <SoftVGA required by setup> THEN

Initialize SoftVGA during VSA initialization

Jump to integrated graphics BIOS for initialization

ENDIF

4.5.1.1Monochrome Support

GeodeROM includes the appropriate INT 10h support for monochrome video adapters.

SoftVG needs an extra hole at B000h-B7FFh when a mono card is present.

4.5.1.2Dual Monitor Support

GeodeROM provides dual monitor support. GeodeROM assumes that the external card is the primary graphics card and that the XpressGRAPHICS™ system is secondary.

AMD Geode™ GX Processor/CS5535 Companion Device GeodeROM Porting Guide

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Contents Publication ID 32430C AprilTrademarks Advanced Micro Devices, Inc. All rights reservedContents Contents GeodeLink Architecture Topology List of FiguresList of Figures List of Tables List of Tables Introduction Overview1Assumption Example MSR Transaction Model Specific Registers2Load MSR specified by ECX into Edxeax Write the value in Edxeax to MSR specified by ECXModel Specific Registers AMD Geode GeodeLink Architecture3GX Processor CS5535 Companion DeviceDescriptors GeodeLink MSR AddressingAddressing Example Memory Descriptor TypesProcessor Initialization Set Clocks and ResetSysref Mdiv VdivMemory Controller Initialization Calculating Processor SpeedCPU Identification GeodeLink Modules Initialization Test Extended DramSize Memory Default Region Configuration Properties Bit Descriptions Descriptor Allocation Glpci RegionsDescriptor MSR Address Chipset ID AMD Geode CS5535 Companion Device InitializationSet ID Select Idsel Gliu InitializationIRQ Mapper Multi Function General Purpose Timers MFGPTsKeyboard Emulation Logic KEL 1+ System Management Bus SMBusAcpi Power Management LogicFlash Interface Other Legacy DD InitializationATA-5 / Hard Drive Initialization Diverse Device I/O LocationsUniversal Serial Bus USB 7 AC97 Audio Controller InitializationPCI Bus Initialization Virtual System Architecture InitializationGeodeLink Control Processor Initialization Allocate Processor Frame Buffer and VSA2 MemoryInitialize Graphics Subsystem Miscellaneous InitializationsMonochrome Support Dual Monitor Support32430C Clocking Implementation5Scratchpad Initialization Post CodesImplementation Setup Options6 32430C ROM Memory7MapVSA Frame Buffer Memory MappedVSA PCI GeodeROM Flow GX Processor/CS5535 Device VSA Table A-1. Revision History Document Revision HistoryRevision # Revisions / Comments Initial release