sis(4) flow control

Yonghyeon PYUN pyunyh at
Thu Jul 11 00:26:05 UTC 2013

On Thu, Jul 11, 2013 at 12:18:19AM +0200, Andreas Longwitz wrote:
> Yonghyeon PYUN wrote:
> > Hmm, does the change really make flow-control work?
> > I believe flow-control should be negotiated with remote link
> > partner so you have to announce flow-control capability to link
> > partner. In addition, it seems DP83815/DP83816 does not support
> > TX flow-control so it just honors RX pause frames.
> Excuse me, the comment in my patch was wrong. Better would be
>      /* Enable reception of 802.3x pause frames. */.
> My soekris boxes are connected to a slow so called "Ethernet Connect"
> line (2 Mbit/s). The line works correct and stable if I respect incoming
> RX pause frames from the line. I do not need TX flow-control.
> > Try attached patch and let me know how it works.
> Thanks for your patch. I will test it on next update of my soekris boxes
> with sis interfaces. Because they are all remote far away this will need
> some time.

Ok. Make sure to check established link before testing
flow-control. 'ifconfig sis0' will show current media and you
should have something like the following.
  media: Ethernet autoselect <flowcontrol> (100baseTX <full-duplex,flowcontrol,rxpause,txpause>)

If you don't see 'rxpause', re-negotiate flow-control with
'ifconfig sis0 mediaopt flow'.

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