[U-Boot] [PATCH] UEC PHY: Speed up initial PHY neg.

[Detlev Zundel]

Hi Jocke,

>> > Instead of always performing an autoneg, check if the PHY
>> > already has a link and if it matches one of the requested
>> > modes. Initially only 100MbFD is optimized this way.
>>
>> Isn't it about time that we think about _not_ stopping the ethernet
>> device after every transaction?
>
> Hi Detlev
>
> UEC does this already, my patch was to address the initial delay
> you get for the first transaction. Now my PHY based boards gets the link
> up just as quick as Fixed PHY for the first transaction.

Forgive me to not look into this any deeper, but do I understand you
correctly that you do this by essentially no-oping the eth_halt()
function?  Isn't this then effectively violating what net.c expects the
device to do?

I was thinking that net.c itself should not do this continous start/stop
thing as it has problems on many interfaces.  On one ARM machine I've
again seen problems with the MAC address programming because the
eth_halt() resets the controller and so it forgets its address again.
Also the USB-CDC example where the _whole interface_ on the host side is
being torn down after each tftp transfer prompts me to think along this
line.

So in effect I guess my response was rather a ping to Ben, sorry for
that ;)

Cheers
  Detlev

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