On Tue, Sep 17, 2019 at 03:41:01PM +0300, tinywrkb wrote: > On Sun, Sep 15, 2019 at 03:56:52PM +0200, Andrew Lunn wrote: > > > Tinywrkb confirmed to me in private communication that revert of > > > 5502b218e001 fixes Ethernet for him on effected system. > > > > > > He also referred me to an old Cubox-i spec that lists 10/100 Ethernet > > > only for i.MX6 Solo/DualLite variants of Cubox-i. It turns out that > > > there was a plan to use a different 10/100 PHY for Solo/DualLite > > > SOMs. This plan never materialized. All SolidRun i.MX6 SOMs use the same > > > AR8035 PHY that supports 1Gb. > > > > > > Commit 5502b218e001 might be triggering a hardware issue on the affected > > > Cubox-i. I could not reproduce the issue here with Cubox-i and a Dual > > > SOM variant running v5.3-rc8. I have no Solo/DualLite variant handy at > > > the moment. > > > > Could somebody with an affected device show us the output of ethtool > > with and without 5502b218e001. Does one show 1G has been negotiated, > > and the other 100Mbps? If this is true, how does it get 100Mbps > > without that patch? We are missing a piece of the puzzle. > > > > Andrew > > linux-test-5.1rc1-a2703de70942-without_bad_commit > > Settings for eth0: > Supported ports: [ TP MII ] > Supported link modes: 10baseT/Half 10baseT/Full > 100baseT/Half 100baseT/Full > 1000baseT/Full So this means the local device says it can do 1000Mbps. > Supported pause frame use: Symmetric > Supports auto-negotiation: Yes > Supported FEC modes: Not reported > Advertised link modes: 10baseT/Half 10baseT/Full > 100baseT/Half 100baseT/Full > 1000baseT/Full The link peer can also do 1000Mbps. > Advertised pause frame use: Symmetric > Advertised auto-negotiation: Yes > Advertised FEC modes: Not reported > Link partner advertised link modes: 10baseT/Half 10baseT/Full > 100baseT/Half 100baseT/Full > 1000baseT/Full > Link partner advertised pause frame use: Symmetric > Link partner advertised auto-negotiation: Yes > Link partner advertised FEC modes: Not reported > Speed: 100Mb/s Yet they have decided to do 100Mbps. We need to understand Why? The generic PHY driver would not do this on its own. So i'm thinking something has poked a PHY register with some value, and this patch is causing it to be over written. Please can you use mii-tool -v -v to dump the PHY registers in each case. Thanks Andrew