Re: [PATCH] phy: smsc: Implement .aneg_done callback for LAN8720Ai

From: Lukasz Majewski
Date: Wed Apr 12 2023 - 07:26:18 EST


Hi Andrew,

> On Thu, Apr 06, 2023 at 03:48:43PM +0200, Simon Horman wrote:
> > On Thu, Apr 06, 2023 at 03:11:27PM +0200, Lukasz Majewski wrote:
> > > The LAN8720Ai has special bit (12) in the PHY SPECIAL
> > > CONTROL/STATUS REGISTER (dec 31) to indicate if the
> > > AutoNeg is finished.
> > >
> > > Signed-off-by: Lukasz Majewski <lukma@xxxxxxx>
> >
> > Hi Lukasz,
> >
> > I think you need to rebase this on net-next.
> >
> > If you repost please also include 'net-next' in the subject:
> > [PATCH net-next v2].
> >
> > And a note about the changes between v1 and v2.
>
> This actually seems like a fix. So it should probably be based on net,
> and have a Fixes: tag.

I've rebased it on the newest vanila kernel.

And this patch come from the work on LAN8720Ai based system (speed up
of the boot time).

It turned out that this IC has a dedicated bit (in vendor specific
register) to show explicitly if auto neg is done.

>
> Lukasz, how does this bit differ to the one in BMSR?

In the BMSR - bit 5 (Auto Negotiate Complete) - shows the same kind of
information.

The only difference is that this bit is described as "Auto
Negotiate Complete" and the bit in this patch indicates "Auto
Negotiation Done".

> Is the BMSR bit
> broken?

This bit works as expected.

> Is there an errata for this?

No, errata doesn't mention it.

I just was wondering if shall we do use the "vendor specific"
indication bit or the "standard one" from BMSR register.

I try to figure out why SMSC put bit from this patch in the SoC...

> It would be good to describe the
> problem you see which this patch fixes.
>
> Andrew




Best regards,

Lukasz Majewski

--

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