> On Thu, Mar 26, 2020 at 03:51:16PM +0200, Florinel Iordache wrote: > > Add support for backplane kr phy connection types currently available > > (10gbase-kr, 40gbase-kr4) and the required phylink updates (cover all > > the cases for KR modes which are clause 45 compatible to correctly > > assign phy_interface and phylink#supported) > > > > Signed-off-by: Florinel Iordache <florinel.iordache@xxxxxxx> > > --- > > drivers/net/phy/phylink.c | 15 ++++++++++++--- > > include/linux/phy.h | 6 +++++- > > 2 files changed, 17 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c > > index fed0c59..db1bb87 100644 > > --- a/drivers/net/phy/phylink.c > > +++ b/drivers/net/phy/phylink.c > > @@ -4,6 +4,7 @@ > > * technologies such as SFP cages where the PHY is hot-pluggable. > > * > > * Copyright (C) 2015 Russell King > > + * Copyright 2020 NXP > > */ > > #include <linux/ethtool.h> > > #include <linux/export.h> > > @@ -303,7 +304,6 @@ static int phylink_parse_mode(struct phylink *pl, struct > fwnode_handle *fwnode) > > break; > > > > case PHY_INTERFACE_MODE_USXGMII: > > - case PHY_INTERFACE_MODE_10GKR: > > We might have a backwards compatibility issue here. If i remember correctly, > there are some boards out in the wild using PHY_INTERFACE_MODE_10GKR not > PHY_INTERFACE_MODE_10GBASER. > > See e0f909bc3a242296da9ccff78277f26d4883a79d > > Russell, what do you say about this? > > Andrew Ethernet interface nomenclature is using the following terminology: e.g. 10GBase-KR: data rate (10G), modulation type (Base = Baseband), medium type (K = BacKplane), physical layer encoding scheme (R = scRambling/descRambling using 64b/66b encoding that allows for Ethernet framing at a rate of 10.3125 Gbit/s) So 10GBase-R name provide information only about the data rate and the encoding scheme without specifying the interface medium. 10GBase-R is a family of many different standards specified for several different physical medium for copper and optical fiber like for example: 10GBase-SR: Short range (over fiber) 10GBase-LR: Long reach (over fiber) 10GBase-LRM: Long reach multi-mode (over fiber) 10GBase-ER: Extended reach (over fiber) 10GBase-CR: 10G over copper 10GBase-KR: Backplane 10GBase-KR represents Ethernet operation over electrical backplanes on single lane and uses the same physical layer encoding as 10GBase-LR/ER/SR defined in IEEE802.3 Clause 49. So prior to my change, phy_interface_t provided both enumerators which is correct: PHY_INTERFACE_MODE_10GBASER PHY_INTERFACE_MODE_10GKR Perhaps PHY_INTERFACE_MODE_10GKR was not used before because Backplane support was not available and all 10GBase-R family of interfaces should be using PHY_INTERFACE_MODE_10GBASER. In case PHY_INTERFACE_MODE_10GKR was used before, this is probably incorrect and should be changed for those boards to use the correct phy connection type: PHY_INTERFACE_MODE_10GBASER. Moreover now I also introduced a new phy connection type to cover also: 40GBase-KR4 which is 40G Backplane over 4-lanes: PHY_INTERFACE_MODE_40GKR4 Prior to adding backplane support, 10GKR case was handled the same as 10GBASER in phylink_parse_mode. But now because we are adding support for backplane modes, all backplane phy connection types (like: 10GKR, 40GKR4) must be treated separately to correctly setup the supported phylink. Florin.
