[EXT] Re: [PATCH v1 2/5] net: phy: marvell: extend 88E2110 to use both 2.5GHz modes

[Stefan Chulski]

> > >
> > > SGMII uses the same coding as 1000base-x, but the latter works only
> > > with one speed (1000mbps), while the former can also work in 10mbps
> > > and 100mbps (by repeating each byte 100 or 10 times, respectively).
> > >
> > > Then there is 2500base-x, which is the same as 1000base-x, but with
> > > the clock being at 2.5x the speed of 1000base-x clock.
> > >
> > > But there is no analogue of the SGMII protocol (i.e. the repearing
> > > of bytes in order to achieve lower speed) for the 2500base-x.
> > >
> > > So what I am confused about here is what is supposed to be the
> > > difference between
> > >   PHY_INTERFACE_MODE_SGMII_2500
> > > and
> > >   PHY_INTERFACE_MODE_2500BASEX
> > > ?
> > >
> > > Marek
> 
> I not sure what is correct naming for these mode. PHY_INTERFACE includes
> both MAC2PHY interfaces(MII, RGMII and etc), PHY2PHY interfaces(like
> BASEX) and SGMII(which is kind of both).
> For both 2500BASEX and SGMII_2500 Serdes lanes set to HS-SGMII in 3.125G
> speed, but MAC configured differently and autoneg cannot be supported.
> 
> Regards,
> Stefan.

Since we already has PHY_INTERFACE_MODE_SGMII and PHY_INTERFACE_MODE_QSGMII (5G mode), maybe we should call
PHY_INTERFACE_MODE_HSGMII - High-Serial Gigabit Media Independent Interface (HSGMII, 3.125Gbps).

Regards,
Stefan.