> > From: Tristram Ha <tristram.ha@xxxxxxxxxxxxx> > > > > The SGMII module of KSZ9477 switch can be setup in 3 ways: 0 for direct > > connect, 1 for 1000BaseT SFP, and 2 for 10/100/1000 SFP. > > > > SFP is typically used so the default is 1. The driver can detect > > 10/100/1000 SFP and change the mode to 2. For direct connect this mode > > has to be explicitly set to 0 as driver cannot detect that > > configuration. > > Could you explain this in more detail. Other SGMII blocks don't need > this. Why is this block special? > > Has this anything to do with in-band signalling? There are 2 ways to program the hardware registers so that the SGMII module can communicate with either 1000Base-T/LX/SX SFP or 10/100/1000Base-T SFP. When a SFP is plugged in the driver can try to detect which type and if it thinks 10/100/1000Base-T SFP is used it changes the mode to 2 and program appropriately.
