Subject: Re: [PATCH net-next v2 4/4] net: mvpp2: 2500baseX support

From: Antoine Tenart <[email-masked]>
Date: Wed, 3 Jan 2018 16:32:27 +0100

Hi Andrew,

On Wed, Jan 03, 2018 at 04:20:36PM +0100, Andrew Lunn wrote:
> > @@ -4612,6 +4616,9 @@ static int mvpp22_comphy_init(struct mvpp2_port *port)
> >  	case PHY_INTERFACE_MODE_1000BASEX:
> >  		mode = PHY_MODE_SGMII;
> >  		break;
> > +	case PHY_INTERFACE_MODE_2500BASEX:
> > +		mode = PHY_MODE_2500SGMII;
> > +		break;
> 
> I think this is the source of confusion with linux/phy.h and
> linux/phy/phy.h.
> 
> What would PHY_INTERFACE_MODE_2500SGMII use?
> 
> Where is this all getting confused? Should the caller to
> mvpp22_comphy_init() actually be passing PHY_INTERFACE_MODE_2500SGMII?
> What is the MAC actually doing at this point? 2500BASEX or 2500SGMII?

PHY_INTERFACE_MODE_2500BASEX is the PHY mode whereas PHY_MODE_2500SGMII
is the mode used by the common PHY driver (i.e. the one configuring the
serdes lanes).

There's no PHY_INTERFACE_MODE_2500SGMII mode.

> At minimum there needs to be a comment that this is not a typ0,
> otherwise you are going to get patches submitted to 'fix' this.

Sure, I can add a comment to state this function is a translation
between the net PHY mode and the generic PHY mode (it's a n-to-1
translation).

Thanks!
Antoine

-- 
Antoine Ténart, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com