On 2019-06-03 11:37 p.m., Heiner Kallweit wrote: >> + /* Xilinx PHY wrongly indicates BMSR_ESTATEN = 0 even though >> + * extended status registers are supported. So we force the PHY >> + * features to PHY_GBIT_FEATURES in order to allow gigabit support >> + * to be detected. >> + */ >> + .features = PHY_GBIT_FEATURES, > > BMSR_ESTATEN is used by genphy_config_advert() too. Means you would > need to implement your own config_aneg callback and basically > copy 99% of genphy_config_advert(). > > I think the better alternative is to implement a quirk flag in phylib > similar to PHY_RST_AFTER_CLK_EN. Let me come up with a proposal. > > Last but not least: Not setting BMSR_ESTATEN for a GBit PHY violates > the standard. Any intention from Xilinx to fix this?
My apologies, it seems like my initial diagnosis of this was incorrect. ESTATEN is indeed set to 1. The problem is that in the configuration of the PHY that we are using, which is set up for 1000Base-X mode, ESTATUS returns 0x8000 indicating support for 1000Base-X full duplex and not ESTATUS_1000_TFULL or ESTATUS_1000_THALF, which are the only bits that genphy_config_init checks for. Therefore, genphy_config_init comes back with no modes supported for the PHY, and phydev therefore rejects attaching the PHY to the network device. Adding PHY_GBIT_FEATURES in causes 1000Base-T half and full duplex to be added into the mix, which fakes things out enough for it to work, it appears. So it seems like what is missing is the ability of genphy_config_init to detect the bits in the extended status register for 1000Base-X and add the corresponding mode flags. It appears bit 15 for 1000Base-X full duplex is standardized in 802.3 Clause 22, so I would expect Linux should be able to detect that and add it as a supported mode for the PHY. genphy_config_init is dealing with the "legacy" 32-bit mode masks that have no bit for 1000BaseX though.. how is that intended to work? -- Robert Hancock Senior Software Developer SED Systems, a division of Calian Ltd. Email: hanc...@sedsystems.ca
