[PATCH] ARM: shmobile: Lager: add Micrel KSZ8041 PHY fixup

Sergei Shtylyov sergei.shtylyov at cogentembedded.com
Thu Sep 26 14:28:31 EDT 2013


Hello.

On 09/26/2013 10:50 AM, Magnus Damm wrote:

>> Currently on the Lager board NFS timeouts/delays are seen when booting.  That
>> turned out to happen because the SoC's ETH_LINK signal turns on and off after
>> each packet.  It is connected to Micrel KSZ8041 PHY's LED0 signal. Ether LEDs
>> on the Lager board are named LINK and ACTIVE which corresponds to non-default
>> 01 setting of the PHY control register 1 bits 14-15. The 'sh_eth' driver resets
>> the PHY when opening the network device, so we have to set the mentioned bits
>> back to 01 from the default 00 value which causes bouncing of ETH_LINK.  That
>> can be achieved using the PHY platform fixup mechanism if we also modify the
>> driver to use it..

>> Signed-off-by: Sergei Shtylyov <sergei.shtylyov at cogentembedded.com>

> Hi Sergei,

> Thanks for your efforts on this. Nice to see that Ethernet for Lager
> board support is improving.

> Can you please share with us with link speeds you tested? I suspect

    100 Mbit/s, full duplex.

> that this patch is only needed for some case, like for instance 100
> MBit Full Duplex.

    Hm, why? :-O

> Fixing the PHY settings makes sense even though only
> a single mode needs it, but knowing which link speeds that are known
> to work would help a lot.

    This patch should not depend on the link speed and duplex settings.

> Cheers,

> / magnus

WBR, Sergei




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