On Mon, Oct 19, 2020 at 09:32:56PM +0000, Robert Hancock wrote: > On Mon, 2020-10-19 at 22:08 +0100, Russell King - ARM Linux admin > wrote: > > On Mon, Oct 19, 2020 at 02:49:13PM -0600, Robert Hancock wrote: > > > The Finisar FCLF8520P2BTL 1000BaseT SFP module uses a Marvel > > > 81E1111 PHY > > > > You mean 88E1111 here. > > > > Whoops, will fix in an updated version. > > > > with a modified PHY ID, and by default does not have 1000BaseX > > > auto-negotiation enabled, which is not generally desirable with > > > Linux > > > networking drivers. Add handling to enable 1000BaseX auto- > > > negotiation. > > > Also, it requires some special handling to ensure that 1000BaseT > > > auto- > > > negotiation is enabled properly when desired. > > > > > > Based on existing handling in the AMD xgbe driver and the > > > information in > > > the Finisar FAQ: > > > https://can01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.finisar.com%2Fsites%2Fdefault%2Ffiles%2Fresources%2Fan-2036_1000base-t_sfp_faqreve1.pdf&data=04%7C01%7Crobert.hancock%40calian.com%7C6eda7d636fbf4a70ff2408d8747332a2%7C23b57807562f49ad92c43bb0f07a1fdf%7C0%7C0%7C637387385403382018%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=cfChA4TBw3f70alrANXPR0HHgNg3Vs%2FNeEYhzZc%2BF9A%3D&reserved=0 > > > > There's lots of modules that have the 88E1111 PHY on, and we switch > > it to SGMII mode if it's not already in SGMII mode if we have access > > to it. Why is your setup different? > > This is in our setup using the Xilinx axienet driver, which is stuck > with whatever interface mode the FPGA logic is set up for at synthesis > time. In our case since we need to support fiber modules, that means we > are stuck with 1000BaseX mode with the copper modules as well.
Hmm, okay. > Note that there is some more work that needs to be done for this to > work completely, as phylink currently will only attempt to use SGMII > with copper modules and fails out if that's not supported. I have a > local patch that just falls back to trying 1000BaseX mode if the driver > reports SGMII isn't supported and it seems like it might be a copper > module, but that is a bit of a hack that may need to be handled > differently. I have worked on patches that implement a replacement system of working out which interface mode to use, not only for optical modules, but also for PHYs as well. It needs network drivers and PHYs to advertise a bitmap of which PHY_INTERFACE_MODE_xxx each support, and we use an ordered list of preferred modes to find the most suitable interface mode supported by both the network driver and the module/PHY. I never fully finished the patches though. PHYs need to fill in this bitmap before they are bound to a network driver, because we need to work out which interface mode to use before we can attach the PHY. The patches for this are in my net-queue branch on git://git.armlinux.org.uk/~rmk/linux-arm.git/ -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!
