Le 13/11/2016 à 11:51, Mason a écrit : > On 13/11/2016 04:09, Andrew Lunn wrote: > >> Mason wrote: >> >>> When connected to a Gigabit switch >>> 3.4 negotiates a LAN DHCP setup instantly >>> 4.7 requires over 5 seconds to do so >> >> When you run tcpdump on the DHCP server, are you noticing the first >> request is missing? >> >> What can happen is the dhclient gets started immediately and sends out >> its first request before auto-negotiation has finished. So this first packet >> gets lost. The retransmit after a few seconds is then successful. > > I will run tcpdump on the server as I run udhcpc on the client > for Linux 3.4 vs 4.7 > > Do you know what would make auto-negotiation fail at 100 Mbps > on 4.7? (whereas it succeeds on 3.4) > > (Thinking out loud) If the problem were in auto-negotiation, > then if should work if I hard-code speed and duplex using > ethtool, right? (IIRC, hard-coding doesn't help.)
I would start with checking basic things: - does your Ethernet driver get a link UP being reported correctly (netif_carrier_ok returns 1)? - if you let the bootloader configure the PHY and utilize the Generic PHY driver instead of the Atheros PHY driver, does the problem appear as well? - what do transmit/receive counters on the Ethernet driver/MAC return? -- Florian
