Messages in this thread | | | From | Tim Harvey <> | Date | Wed, 12 Jan 2022 10:25:45 -0800 | Subject | Re: [PATCH net-next v6] net: phy: intel-xway: Add RGMII internal delay configuration |
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On Wed, Jan 12, 2022 at 5:46 AM Russell King (Oracle) <linux@armlinux.org.uk> wrote: > > On Tue, Jan 11, 2022 at 11:12:33AM -0800, Tim Harvey wrote: > > I added a debug statement in xway_gphy_rgmii_init and here you can see > > it gets called 'before' the link comes up from the NIC on a board that > > has a cable plugged in at power-on. I can tell from testing that the > > rx_delay/tx_delay set in xway_gphy_rgmii_init does not actually take > > effect unless I then bring the link down and up again manually as you > > indicate. > > > > # dmesg | egrep "xway|nicvf" > > [ 6.855971] xway_gphy_rgmii_init mdio_thunder MDI_MIICTRL:0xb100 > > rx_delay=1500 tx_delay=500 > > [ 6.999651] nicvf, ver 1.0 > > [ 7.002478] nicvf 0000:05:00.1: Adding to iommu group 7 > > [ 7.007785] nicvf 0000:05:00.1: enabling device (0004 -> 0006) > > [ 7.053189] nicvf 0000:05:00.2: Adding to iommu group 8 > > [ 7.058511] nicvf 0000:05:00.2: enabling device (0004 -> 0006) > > [ 11.044616] nicvf 0000:05:00.2 eth1: Link is Up 1000 Mbps Full duplex > > Does the kernel message about the link coming up reflect what is going > on physically with the link though? > > If a network interface is down, it's entirely possible that the link is > already established at the hardware level, buit the "Link is Up" message > gets reported when the network interface is later brought up. So, > debugging this by looking at the kernel messages is unreliable. >
Russell,
You are correct... the link doesn't come up at that point its already linked. So we need to force a reset or an auto negotiation reset after modifying the delays.
Tim
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