mlx5en - PTYS reg - eth_proto_oper bit 19 not defined

[Konstantin Belousov]

On Fri, Feb 07, 2020 at 02:15:53PM -0500, Adam Peace wrote:
> Hello,
> 
> I'm using the mlx5en driver that's in the FreeBSD 11.3 tree for a Mellanox
> ConnectX-4 ethernet card on an Azure VM.
> 
> The problem that I'm seeing is that the value being retrieved from the PTYS
> register for eth_proto_oper is 0x80000, which is bit 19 of the field, but a
> value for bit 19 is not defined in the mlx5e_link_speed enum. This causes
It is 50GBase-KR4 whatever this means.

> the driver to not find an entry in the mlx5e_mode_table and the
> media.subtype and media.baudrate are not set. This does not stop the
> mlx5en.ko module from loading, but network connectivity is affected.
> 
> It seems that this enum is phased out in the upstream Linux driver, but
> it's not clear to me how the replacement method works. Is this a known
> issue? It seems that FreeBSD 12.1 and master still use the method that's
> used in 11.3. Does anyone have any insight on this?

The problem seems to be that net/if_media.h does not pre-define this mode.
It is somewhat larger patch than just adding the entry in the table in the
driver.