[PATCH 1/3][v2] net: phy: introduce 1000BASE-KX and 10GBASE-KR

[Shaohui Xie]

_______________________________________
From: Andrew Lunn <andrew at lunn.ch>
Sent: Friday, January 22, 2016 5:12 AM
To: Shaohui Xie
Cc: Sebastian Hesselbarth; Florian Fainelli; shh.xie at gmail.com; devicetree at vger.kernel.org; netdev at vger.kernel.org; linuxppc-dev at lists.ozlabs.org; davem at davemloft.net; Shaohui Xie
Subject: Re: [PATCH 1/3][v2] net: phy: introduce 1000BASE-KX and 10GBASE-KR

On Tue, Jan 19, 2016 at 05:00:35AM +0000, Shaohui Xie wrote:
> > -----Original Message-----
> > From: Andrew Lunn [mailto:andrew at lunn.ch]
> > Sent: Monday, January 18, 2016 11:15 PM
> > To: Shaohui Xie
> > Cc: Sebastian Hesselbarth; Florian Fainelli; shh.xie at gmail.com;
> > devicetree at vger.kernel.org; netdev at vger.kernel.org; linuxppc-
> > dev at lists.ozlabs.org; davem at davemloft.net; Shaohui Xie
> > Subject: Re: [PATCH 1/3][v2] net: phy: introduce 1000BASE-KX and 10GBASE-KR
> >
> > > [S.H] the fsl backplane, e.g. 10GBASE-KR, needs software to handle
> > > link training, It's to train link partner, and trained by link partner
> > parallel.
> > >
> > > But if media type is not copper, e.g. optical module, we won't need this.
> >
> > So what we actually need to know is copper vs fibre?

> Copper is not enough to indicate backplane, since backplane is
> always copper, but copper is not always backplane.

>O.K, lets try again....

[S.H]Seems I did not get your point, Sorry for the inconvenient.

>If it is copper backplane you need to perform training.

>Looking at the driver probe function, it is either 1000BASE-KX, no
>training needed, or else it is 10GBASE-RK and training is needed.

>Looking at fsl_backplane_config_aneg() you expect phydev->speed to be
>set, and from the speed you then kick of either KR autoneg or KX
>autoneg. Could you also start the training at this point? Use the
>speed to indicate if training is needed?

 [S.H]The training cannot be started at this point, yet, because it's based on 
autoneg result, only when both sides autoneg-ed to 10G-KR, then to start
the training.

Besides the driver, generally speaking, "copper + speed" is not enough to indicate 
it's backplane, for ex. "copper + 1000" does not mean it has to be 1000BASE-KX, 
it could be SGMII, hence cannot use KX autoneg.

If putting backplane property to phy.txt is not good, I can put it to fsl specific
binding, like the second patch 2/3 did.

Thank you!
Shaohui