Re: [PATCH net-next v3] net: phy: micrel: add phy-mode support for the KSZ9031 PHY

From: Philippe Schenker
Date: Tue Apr 07 2020 - 08:34:10 EST


On Tue, 2020-04-07 at 13:02 +0200, Marc Kleine-Budde wrote:
> On 4/7/20 12:57 PM, Philippe Schenker wrote:
> > On Tue, 2020-04-07 at 11:36 +0200, Oleksij Rempel wrote:
> > > Add support for following phy-modes: rgmii, rgmii-id, rgmii-txid,
> > > rgmii-rxid.
> > >
> > > This PHY has an internal RX delay of 1.2ns and no delay for TX.
> > >
> > > The pad skew registers allow to set the total TX delay to max
> > > 1.38ns
> > > and
> > > the total RX delay to max of 2.58ns (configurable 1.38ns + build
> > > in
> > > 1.2ns) and a minimal delay of 0ns.
> > >
> > > According to the RGMII v1.3 specification the delay provided by
> > > PCB
> > > traces
> > > should be between 1.5ns and 2.0ns. The RGMII v2.0 allows to
> > > provide
> > > this
> > > delay by MAC or PHY. So, we configure this PHY to the best values
> > > we
> > > can
> > > get by this HW: TX delay to 1.38ns (max supported value) and RX
> > > delay
> > > to
> > > 1.80ns (best calculated delay)
> > >
> > > The phy-modes can still be fine tuned/overwritten by *-skew-ps
> > > device tree properties described in:
> > > Documentation/devicetree/bindings/net/micrel-ksz90x1.txt
> > >
> > > Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
> >
> > Make sure you do not exceet 80 chars with your phydev_warn. Besides
> > that:
>
> Warning and Error strings should not be wrapped, so that you can
> better
> "grep" for them.

Didn't knew that, thanks!
>
> regards,
> Marc
>