i installed the debian image, the one in the wiki, and the sfp ont is working here !
But i want to use Openwrt !!! 
I think there’s an issue with the mtk_soc_eth driver. It doesn’t seem to be allowed anymore to set fixed speed/duplex on sfp (1000baseX/Full).
Just says Speed/Duplex Unknown when autoneg is turned off.
ethtool eth1
Settings for eth1:
Supported ports: [ FIBRE ]
Supported link modes: 1000baseX/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: 1000baseX/Full
Advertised pause frame use: Symmetric Receive-only
Advertised auto-negotiation: No
Advertised FEC modes: Not reported
Speed: Unknown!
Duplex: Unknown! (255)
Auto-negotiation: off
Port: FIBRE
PHYAD: 0
Transceiver: internal
Current message level: 0x000000ff (255)
drv probe link timer ifdown ifup rx_err tx_err
When attempting to fix it… it doesn’t do anything:
ethtool -s eth1 autoneg off speed 1000 duplex full
root@OpenWRT:/# ethtool eth1
Settings for eth1:
Supported ports: [ FIBRE ]
Supported link modes: 1000baseX/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: 1000baseX/Full
Advertised pause frame use: Symmetric Receive-only
Advertised auto-negotiation: No
Advertised FEC modes: Not reported
Speed: Unknown!
Duplex: Unknown! (255)
Auto-negotiation: off
Port: FIBRE
PHYAD: 0
Transceiver: internal
Current message level: 0x000000ff (255)
drv probe link timer ifdown ifup rx_err tx_err
Link detected: yes