Power off for PCI devices
johannes.hofmann at gmx.de
Wed Sep 10 13:51:01 PDT 2008
Hasso Tepper <hasso at estpak.ee> wrote:
> Johannes Hofmann wrote:
>> Nice! Do the modules have to be loaded (and then unloaded) for this to
>> take effect or is it enough to just not load them in the first place?
> It was enough to just not load them even before this patch. Powering down
> not used devices at boot time was already there with this commit:
> This patch adds just the ability to power down a devices on module unload.
Ah ok. Is there a way to verify the state of the pci devices?
On my T42 thinkpad I don't see any difference in power consumption
with hw.pci.do_power_nodriver=1 (measured with an external device and
battery removed). I'm always around 20 Watt, with est enabled,
"DynamicClocks" "on" in xorg.conf, and screen backlight set to the
lowest possible value.
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