NAME
dfs —
Dynamic Frequency Switching
SYNOPSIS
dfs* at macgpio?
DESCRIPTION
The dfs driver provides support for the
Dynamic Frequency Switching feature found on some PowerPC
microprocessors.
It conserves power by lowering the processor operating frequency. Depending on the processor model, the processor-to-system bus ratio can be divided by two or four.
HARDWARE
Processors supported by the dfs driver are
part of the PowerPC G4 family and are found on various iBook and PowerBook
machines:
MPC7447A PowerPC 7447 "Apollo 7" MPC7448 PowerPC 7448 "Apollo 8"
SEE ALSO
MPC7450 RISC Microprocessor Family Reference Manual.
HISTORY
Support for the dfs driver first appeared
in OpenBSD 5.0.