Re: [PATCH net-next 5/5] net: dsa: b53: Add SerDes support

[Florian Fainelli <f.fainelli@gmail.com>]

On 09/04/2018 04:15 PM, Andrew Lunn wrote:
> On Tue, Sep 04, 2018 at 03:11:20PM -0700, Florian Fainelli wrote:
>> Add support for the Northstar Plus SerDes which is accessed through a
>> special page of the switch. Since this is something that most people
>> probably will not want to use, make it a configurable option.
>>
>> The SerDes supports both SGMII and 1000baseX modes, and is internally
>> looking like a seemingly standard MII PHY, except for the few bits that
>> got repurposed.
> 
> Hi Florian
> 
> The SERDES in the 6352 also look very similar to a standard MII PHYs.
> 
> Maybe at some point, we should look at the SERDES drivers we have
> embedded in different MAC drivers, and see if we can pull them out,
> maybe put them in drivers/net/phy. Any SERDES driver being used in
> combination with phylink probably has the same API.

Yes, that would sound like a good move forward. The SerDes on the
Northstar Plus does have a bunch of MII standard registers, but not a
whole lot (BMSR, BMCR, MII_PHYSID1/2, AUTONEGADV, AUTONEGLPABIL) and
then, it's all custom.

It would be good to have possibly a third vendor (Mediatek? Qualcomm?)
and see how they did it so we can define an appropriate API.
-- 
Florian