Kinda upset at the lack of response to GBe issues

[tkaiser]

what a normal software tool at the startup can do a workaround for the GbE problem

We were at this stage since the early days and ethtool has been included into some OS images for exactly and only this reason: http://forum.pine64.org/showthread.php?t...ol#pid5947

Back at that time none of the developers was able to reproduce the issue (both 1GB developer samples that arrived here never showed any problems regarding GbE and I tried it out against 2 GbE routers and 4 different GbE switches) and unfortunately back at that time a few other Ethernet issues existed (Android never booting when Ethernet cable connected on first boot, Ethernet driver crashing in Linux on 2 GB boards and so on) and also unfortunately even moderators all the time suggested the wrong things to users ('Use the workaround! Don't help us nail the problem down!)

So what we need now is someone collecting clear descriptions of the issue ruling out the other potential issues that lead to horribly low iperf numbers first (just like you did!).

GbE works completely different at the PHY layer than Fast Ethernet, that's also the reason why auto-negotiation is mandatory with GbE since there 2 connected GbE PHYs have to establish a master <--> slave connection and sync their clocks and so on. If anything happens at this point for whatever reasons the symptoms so many are telling are normal. I experienced stuff like that maybe 10 years ago at a customer where the local admin followed advises from last century, disabled auto-negotiation on the new GbE switch and all sorts of bad things happened.

I hope that I can reproduce the issue when your board arrives. But if two minor issues are combined (instable clock here and missing negotiation there) weird things might happen and maybe your board will work here without any problems. Let's see. In the meantime quoting the IEEE standard:

All 1000BASE-T PHYs shall provide support for Auto-Negotiation
(Clause 28) and shall be capable of operating as MASTER or SLAVE.
Auto-Negotiation is performed as part of the initial set-up of the link, and
allows the PHYs at each end to advertise their capabilities (speed, PHY
type, half or full duplex) and to automatically select the operating mode
for communication on the link. Auto-negotiation signaling is used for the
following two primary purposes for 1000BASE-T:

a) To negotiate that the PHY is capable of supporting 1000BASE-T half
duplex or full duplex transmission.

b) To determine the MASTER-SLAVE relationship between the PHYs at
each end of the link. 1000BASE-T MASTER PHY is clocked from a local source.
The SLAVE PHY uses loop timing where the clock is recovered from the received data stream.