Re: Ethtool is missing C2C link modes

On Tue, Jul 21, 2026 at 11:29:05PM +0000, Srinivasan, Vijay wrote:

quoted

As for your comment/question about FW vs linux controiling the HW, the intent here
is to use linux to tell FW where to go based on user input.
How the link is eventually achieved is all in FW.  

quoted

I don't see how that works. ethtool has no APIs around
phy_interface_t.  All ethtool offers is link modes. How do you see
this working?

Correct me if I am wrong but isn't that the role of the driver?  
I expect device driver to translate Ethtool link mode argument and pass it to 
FW via driver-FW handshake (device specific SET/GET functions). 
MAC and PHY config. which includes phy_interface_t for that specific link speed 
is then implicitly handled by FW. No other intervention from user should be 
required.

It is. But if the driver is talking to firmware, it is using whatever
proprietary values defined by the firmware.

It only makes sense to use phy_interface_t for communication between
different Linux components, or uAPI and a Linux component.

	  Andrew