[patch] WOL support for nfe(4)

[Pyun YongHyeon]

On Thu, Nov 11, 2010 at 08:08:25AM +0100, Yamagi Burmeister wrote:
> On Wed, 10 Nov 2010, Pyun YongHyeon wrote:
> 
> >On Tue, Nov 09, 2010 at 01:34:21PM -0800, Pyun YongHyeon wrote:
> >>On Tue, Nov 09, 2010 at 10:01:36PM +0100, Yamagi Burmeister wrote:
> >>>On Tue, 9 Nov 2010, Pyun YongHyeon wrote:
> >>>
> >>>>>No, the link stays at 1000Mbps so the driver must manually switch back
> >>>>>to 10/100Mbps.
> >>>>>
> >>>>
> >>>>Hmm, this is real problem for WOL. Establishing 1000Mbps link to
> >>>>accept WOL frames is really bad idea since it can draw more power
> >>>>than 375mA. Consuming more power than 375mA is violation of
> >>>>PCI specification and some system may completely shutdown the power
> >>>>to protect hardware against over-current damage which in turn means
> >>>>WOL wouldn't work anymore. Even if WOL work with 1000Mbps link for
> >>>>all nfe(4) controllers, it would dissipate much more power.
> >>>>
> >>>>Because nfe(4) controllers are notorious for using various PHYs,
> >>>>it's hard to write a code to reliably establish 10/100Mbps link in
> >>>>driver. In addition, nfe(4) is known to be buggy in link state
> >>>>handling such that forced media selection didn't work well. I'll
> >>>>see what could be done in this week if I find spare time.
> >>>
> >>>Hmm... Maybe just add a hint to the manpage that WOL is possible broken?
> >>
> >>I think this may not be enough. Because it can damage your hardware
> >>under certain conditions if protection circuit was not there.
> >>
> >
> >Ok, I updated patch which will change link speed to 10/100Mps when
> >shutdown/suspend is initiated.  You can get the patch at the
> >following URL. Please give it a try and let me know whether it
> >really changes link speed to 10/100Mbps. If it does not work as
> >expected, show me the dmesg output of your system.
> >
> >http://people.freebsd.org/~yongari/nfe/nfe.wol.patch2
> 
> Okay, that does the trick. At shutdown the link speed is changed to
> 10/100Mbps, at boot - either via WOL magic packet or manuell startup -
> it's changed back to 1000Mbps.
> 

Thanks, patch committed(r215132), will MFC after a week.

> Thanks again,
> Yamagi
> 
> -- 
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