[Intel-wired-lan] [PATCH v1 net-next 1/2] igb: add PHY support for Broadcom 5461S

[Alexander Duyck]

On 05/08/2015 10:46 AM, Andy Gospodarek wrote:
> On Fri, May 8, 2015 at 12:39 PM, Ronciak, John <john.ronciak at intel.com> wrote:
>>> I think we would be willing to take on this task, but I would not like that to be a
>>> gating factor for upstream acceptance of the functionality added with this
>>> patch.  I see that Aaron has commented that no regressions were found with
>>> this patch, but based on current status in patchwork, it looks like Dave is
>>> waiting for something a bit more definitive before accepting it.  Can you ACK it
>>> first so we have support for this platform upstream and then we can go take a
>>> stab at phylib support for igb?
>> So Andy, are you wanting us to accept the patch and that you will then redo things to move to PHYlib in the near future?  What's the time line for that work?  What happens if you guys don't get around to doing it?  This can become very problematic for us as you can imagine.  This also really isn't the upstream way of doing something like this.  So I'm a bit hesitant to do it this way.
>>
>> Can you explain your urgency?
>>
>> Cheers,
>> John
>>
> John,
>
> It is somewhat urgent as we would like to do some upstream kernel
> development on these platforms.  I would rather not have to coach
> everyone/constantly rebase this patch for at least one more kernel
> release and supply it to anyone (internal to Cumulus or outside) just
> to run net-next on these platforms.  Once this is added ONIE kernels
> could also use a pure upstream kernel for booting and installing
> various distros on it, so I see inclusion as a nice feature for the
> community as well.
>
> I was not aware of the patch from Tim Harvey that was adding phylib
> support into igb when I sent the first email, so that may change the
> scope of this effort a bit.  Of course we would now be reliant on that
> patch being included in Dave's tree before we can do our work and that
> appears to have the status of 'changes requested' on the
> intel-wired-lan list, so I see no guarantee that those will be added
> by the time the merge window closes.
>
> Thanks,
>
> -andy

Andy,

The patch as-is seems to have a number of issues since the interface you 
are using has a misconfigured EEPROM.  If you got that addressed you 
could then probably cut down significantly on the code changes needed 
since much of it seems to be just workarounds for stuff that should have 
been taken care of in the EEPROM.  For example, the PHY address and 
external MDIO value are controlled via Initialization Control 3 & 4.  
The configuration for the hardware should be there.  The same goes for 
the LED configuration.  That is something that should start working at 
power-on, not after the driver is loaded.  I really think you should 
work to get those resolved with Quanta then it would probably make your 
driver work much easier.

Also it looks like the bcm5461 is already supported by PHYdev so there 
shouldn't be much to do other than update igb to register a mii_bus, and 
with any luck the PHYdev code already implemented would take care of the 
rest (assuming the EEPROM is fixed).

- Alex