[RFC] net/fs_enet: send a reset request to the PHY on init

Sebastian Andrzej Siewior bigeasy at linutronix.de
Sat Sep 5 01:38:34 EST 2009


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


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