On Tue, Apr 16, 2024 at 04:48:34PM +0100, Russell King (Oracle) wrote: > On Tue, Apr 16, 2024 at 05:43:16PM +0200, Stefan Eichenberger wrote: > > Hi Andrew, > > > > Thanks a lot for the feedback. > > > > On Tue, Apr 16, 2024 at 03:46:19PM +0200, Andrew Lunn wrote: > > > On Tue, Apr 16, 2024 at 02:10:32PM +0200, Stefan Eichenberger wrote: > > > > Add a new device tree property to disable SGMII autonegotiation and > > > > instead use the option to match the SGMII speed to what was negotiated > > > > on the twisted pair interface (tpi). > > > > > > Could you explain this is more detail. > > > > > > SGMII always runs its clocks at 1000Mbps. The MAC needs to duplicate > > > the symbols 100 times when running at 10Mbs, and 10 times when running > > > at 100Mbps. > > > > Currently, the mxl-gpy driver uses SGMII autonegotiation for 10 Mbps, > > 100 Mbps, and 1000 Mbps. For our Ethernet controller, which is on an > > Octeon TX2 SoC, this means that we have to enable "in-band-status" on > > the controller. This will work for all three speed settings. However, if > > we have a link partner that can do 2.5 Gbps, the mxl-gpy driver will > > disable SGMII autonegotiation in gpy_update_interface. This is not > > supported by this Ethernet controller because in-band-status is still > > enabled. Therefore, we will not be able to transfer data at 2.5 Gbps, > > the SGMII link will not go into a working state. > > I have been working on a phylink/phylib patch set to address this. As > I've been busy with health-based appointments during last week and this > week, I haven't been able to spend enough time to get that to a point > that I'm happy to publish it yet. You can find the experimental patches at: http://git.armlinux.org.uk/cgit/linux-arm.git/commit/?h=net-queue&id=0c2fb62db211312ad2f5695997694908b54e9a17 and the three parents to that patch. It's buried in: http://git.armlinux.org.uk/cgit/linux-arm.git/log/?h=net-queue -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!
