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AMD GeodeTM GX1 Processor/
CS5530A Companion Device
Power Management Implementations

1.0 Scope
The intention of this document is to fully describe the power servation action. This method does not require OS (operat-
management features available when designing systems ing system) support because it is handled by SMM
based on the AMD GeodeTM GX1 processor and AMD (System Management Mode) software. Simple monitoring
GeodeTM CS5530A companion device. Once armed with a of external activity is imperfect as well as inefficient.
detailed understanding of the power management features
The second method, called passive power management,
available, the system designer should then be able to
requires the OS to take the active role in managing power.
develop an optimized design from the power consumption
AMD supports two APIs (application programming inter-
standpoint. The AMD GeodeTM SP4GX10 (GX1/CS5530A)
faces) to enable power management by the OS: APM
system platform is used as an example of a specific imple-
(Advanced Power Management) and ACPI (Advanced
mentation for this application note.
Configuration and Power Interface). The extent to which
The GX1 processor and CS5530A companion device con- these resources are employed depends on the application
tain advanced power management features for reducing and the discretion of the system designer.
the power consumption of the system. The hardware
resources provided by a combined GX1/CS5530A-based
system support a full-featured power management imple-
2.1 Power Management Features
mentation. Power management resources can be grouped according
to the function they enable or support. The major functions
The SP4GX10 system platform incorporates a wide range are as follows:
of power management functions and features. Power man-
agement can be enabled through the use of hardware fea- Power States
tures as well as power management-aware software.
Hardware support includes peripheral and activity monitors