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From: Sebastian Andrzej Siewior <bigeasy@linutronix•de>
To: Grant Likely <grant.likely@secretlab•ca>
Cc: linuxppc-dev@ozlabs•org, netdev@vger•kernel.org,
	Vitaly Bordug <vbordug@ru•mvista.com>
Subject: Re: [RFC] net/fs_enet: send a reset request to the PHY on init
Date: Fri, 04 Sep 2009 17:38:34 +0200	[thread overview]
Message-ID: <4AA1347A.5060702@linutronix.de> (raw)
In-Reply-To: <fa686aa40909030948h4acf6d3x1c318baa2fdefe1f@mail.gmail.com>

Grant Likely wrote:
  > What version of the kernel are you using?  The line numbers don't
> match up with kernel mainline, so I wonder if this is before or after
> the OF MDIO rework changes.
It is the kernel which was shipped in ads5121's bsp which is 2.6.24.

> Regardless, this doesn't look right.  It certainly isn't right for the
> driver to do an unconditional PHY reset when it doesn't actually know
> what phy is attached.  For most boards I'm sure this is not desirable
> because it will cause a delay while the PHY auto negotiates.
> Depending on when the first network traffic begins, can cause several
> seconds of boot delay.
> 
> Best would be to do this in U-Boot.  Otherwise, I think I would rather
> see it at phy_device probe time.  At least then it would be on a
> per-phy basis, or could be controlled by a property in the device tree
> so that all boards don't get the same impact.
I have no network support in boot loader so I can't do it there. Doing it 
at phy-probe time sounds reasonable.
So all other boards are doing this kind of reset in u-boot?

> g.
> 


Sebastian

  reply	other threads:[~2009-09-04 15:38 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-09-02 11:04 [RFC] net/fs_enet: send a reset request to the PHY on init Sebastian Andrzej Siewior
2009-09-03 16:48 ` Grant Likely
2009-09-04 15:38   ` Sebastian Andrzej Siewior [this message]
2009-09-04 15:45     ` Grant Likely

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