> > Hi Lucas > > > > Why did you decide to do this, and not add a SUPPORTED_100baseT1? > > > > Could a device support both 100-BASE-T and 100-BASE-T1? If at some > > point we need to differentiate between them, it is going to be > > hard. Especially since this is part of the kernel ABI. > > Networking and especially PHY isn't really my primary area of > expertise, so excuse my ignorance. My reasoning was that we don't > differentiate between 100BASE-T2 and 100BASE-T4 in the kernel today, so > I thought it was fine to handle T1 the same way. > > There are PHYs that can both do regular 100/1000 MBit Ethernet and > 100BASE-T1, but definitely not at the same time or over the same > electrical wiring. 100BASE-T1 is really different in that it uses > capacitive coupling, instead of magnetic like on regular Ethernet. So > it is really a board level decision what gets used and is not something > I would expect to change at runtime.
Hi Lucus http://www.marvell.com/docs/automotive/assets/marvell-automotive-ethernet-88Q5050-product-brief-2017-07.pdf This is a Marvell 8-port switch. It appears it can switch some of its ports between T1, TX, xMII, GMII and SGMII. So maybe an end device is fixed to 100BASE-T1, but it looks like switches could be more flexible. So i think we should be able to differentiate between T1 and TX. We might also need an PHY_INTERFACE_MODE_100BASE_T1. Florian, what do you think? Andrew
