From: Florian Fainelli <f.faine...@gmail.com> > +Russell, > > On 6/4/2019 11:58 AM, Voon Weifeng wrote: > > From: Ong Boon Leong <boon.leong....@intel.com> > > > > xPCS is DWC Ethernet Physical Coding Sublayer that may be integrated > > into a GbE controller that uses DWC EQoS MAC controller. An example of > > HW configuration is shown below:- > > > > <-----------------GBE Controller---------->|<--External PHY chip--> > > > > +----------+ +----+ +---+ +--------------+ > > | EQoS | <-GMII->| DW |<-->|PHY| <-- SGMII --> | External GbE | > > | MAC | |xPCS| |IF | | PHY Chip | > > +----------+ +----+ +---+ +--------------+ > > ^ ^ ^ > > | | | > > +---------------------MDIO-------------------------+ > > > > xPCS is a Clause-45 MDIO Manageable Device (MMD) and we need a way to > > differentiate it from external PHY chip that is discovered over MDIO. > > Therefore, xpcs_phy_addr is introduced in stmmac platform data > > (plat_stmmacenet_data) for differentiating xPCS from 'phy_addr' that > > belongs to external PHY. > > Assuming this DW xPCS can be found with designs other than STMMAC would > not it make sense to model this as some kind of PHY/MDIO bridge? A > little bit like what drivers/net/phy/xilinx_gmii2rgmii.c tries to do?
Yes, DW XPCS is a separate IP that can be sold without the MAC. Thanks, Jose Miguel Abreu
