On Sun, Sep 26, 2004 at 03:34:20PM +0200, Joerg Sonnenberger wrote:
> On Sun, Sep 26, 2004 at 12:17:57PM +0000, Johannes Hofmann wrote:
> > Are there any known problems with the ACPI C3 power saving state? Everything
> > works fine now, as long as I disable the C3 power saving state. If I enable
> > it, the machine locks up as soon as I access the net.
>
> ACPI C2 and C3 doesn't support e.g. USB, because USB wants to access the
> host bus in certain intervals. That might be a good hint :)
Linux version also seems to have an issue(not a lock up though) related to bus
mastering control and has a workaround to stick with C2:
http://ipw2100.sourceforge.net/#issues
(we don't need this since setting cx_lowest=C2 is a sufficient workaround)
PCI bus mastering is disabled to enter C3 state, then re-enabled after
resuming from it. I wonder if you have the same problem on FreeBSD-5.x .