GBit NIC on Nanopi M2
Posted: Sun Nov 20, 2016 4:22 pm
Hello!
I just bought a NanoPi-M2 and installed Debian from scratch, recompiled everything using wiki instructions:
http://wiki.friendlyarm.com/wiki/index.php/NanoPi_M2
I observe problems with the GBit NIC stability, which drops signal after a few minutes. The problem looks exactly like what is described here:
http://linux-sunxi.org/Ethernet
A simple workaround is to reduce the NIC speed to 100mbps with:
ethtool -s eth0 speed 100 duplex full
It is a bit silly not to use the full interface speed. Any idea how this could be improved?
I just bought a NanoPi-M2 and installed Debian from scratch, recompiled everything using wiki instructions:
http://wiki.friendlyarm.com/wiki/index.php/NanoPi_M2
I observe problems with the GBit NIC stability, which drops signal after a few minutes. The problem looks exactly like what is described here:
http://linux-sunxi.org/Ethernet
For reliable Gigabit networking (1000Mbit operation), several sunxi devices require an important tweak that adjusts the relative timing of the clock and data signals to the PHY, in order to compensate for differing trace lengths on the PCB (details). Among others, this includes Banana Pi/Pro, Cubietruck, Lamobo R1, pcDuino3 Nano and Orange Pi/Mini. Recent mainline U-Boot uses CONFIG_GMAC_TX_DELAY to initialize these devices accordingly. If a necessary GMAC TX delay isn't set, then GBit Ethernet operation might be unreliable or won't work at all. 10/100 Mbit/sec negotiation is unaffected, so misconfigured devices could actually work (faster) when connected to a Fast Ethernet port instead of a GBit Ethernet port.
A simple workaround is to reduce the NIC speed to 100mbps with:
ethtool -s eth0 speed 100 duplex full
It is a bit silly not to use the full interface speed. Any idea how this could be improved?