module uhci-hcd and pm

From: Thomas Bettler
Date: Fri Dec 10 2004 - 13:19:42 EST


Hello you all

The uhci-hcd module causes the cpu to work at highest frequecy
(according to x86info -mhz). If I unload it, cpu frequency dropps from full
(1.8GHz) to ~2/3 (1.1GHz). In both cases top shows 97% or even 99% idle.
modprobing it again speeds the cpu up again.

So module uhci-hcd prehibits the cpu clock from saving power on notebooks. (At
least theese with P4-M cpus)

What code forces the cpu to run at high speed? Can I tweak the module to
permit slower cpu speed?

Thomas Bettler

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