Re: [dpdk-dev] Questions about reporting auto-negotiation capability

[Ajit Khaparde <ajit.khaparde@broadcom.com>]

[-- Attachment #1: Type: text/plain, Size: 1351 bytes --]

On Mon, Mar 29, 2021 at 12:19 AM Thomas Monjalon <thomas@monjalon.net> wrote:
>
> 29/03/2021 09:03, Thomas Monjalon:
> > 29/03/2021 06:02, Huisong Li:
> > >          'speed_capa' in struct rte_eth_dev_info is defined as follows:
> > >
> > > uint32_t speed_capa;  /**< Supported speeds bitmap (ETH_LINK_SPEED_). */
> > >
> > >
> > >        Most PMD drivers use this field to report the speeds capability
> > > supported by the device to the upper-layer app.
> > >
> > > But it seems that few NICs report their auto-negotiation capability
> > > through this field. If NIC also uses it to report
> > > their auto-negotiation capability through this field, and should set it
> > > to ETH_LINK_SPEED_AUTONEG(0) based on
> > > the definition of ETH_LINK_SPEED_xxx. In this case, it conflicts the
> > > report of the speeds capability .
> > >
> > > I don't know how to correctly report the auto-negotiation capability of
> > > the device. Thanks for your reply.
> >
> > ETH_LINK_SPEED_AUTONEG is not for capabilities.
> > Anyway, if it is set, it changes nothing (0) in the bitmap.
> > I see mlx5 is wrongly using it.
> >
> > speed_capa is only for enumerating speeds.
>
> I see some drivers are advertising ETH_LINK_SPEED_FIXED in speed_capa
> if the device cannot support autonegotiation.
> Should we add a note in doxygen?
I think we should do that.

>
>