Re: [PATCH net-next 1/6] ethtool: Extend link modes settings uAPI with lanes
From: Andrew Lunn <andrew@lunn.ch>
Date: 2020-10-16 22:15:57
Example:
- swp1 is a 200G port with 4 lanes.
- QSFP28 is plugged in.
- The user wants to select configuration of 100G speed using 2 lanes, 50G each.
$ ethtool swp1
Settings for swp1:
Supported ports: [ FIBRE Backplane ]
Supported link modes: 1000baseT/Full
10000baseT/Full
1000baseKX/Full
10000baseKR/Full
10000baseR_FEC
40000baseKR4/Full
40000baseCR4/Full
40000baseSR4/Full
40000baseLR4/Full
25000baseCR/Full
25000baseKR/Full
25000baseSR/Full
50000baseCR2/Full
50000baseKR2/Full
100000baseKR4/Full
100000baseSR4/Full
100000baseCR4/Full
100000baseLR4_ER4/Full
50000baseSR2/Full
10000baseCR/Full
10000baseSR/Full
10000baseLR/Full
10000baseER/Full
50000baseKR/Full
50000baseSR/Full
50000baseCR/Full
50000baseLR_ER_FR/Full
50000baseDR/Full 100000baseKR2/Full
100000baseSR2/Full
100000baseCR2/Full
100000baseLR2_ER2_FR2/Full
100000baseDR2/Full
I'm not sure i fully understand all these different link modes, but i
thought these 5 are all 100G using 2 lanes? So why cannot the user
simply do
ethtool -s swp1 advertise 100000baseKR2/Full
and the driver can figure out it needs to use two lanes at 50G?
Andrew