Re: [PATCH net-next 5/6] arm64: dts: marvell: mcbin: enable the fourth network interface

From: Antoine Tenart <antoine.tenart@free-electrons.com>
To: Florian Fainelli <f.fainelli@gmail.com>
Cc: Antoine Tenart <antoine.tenart@free-electrons.com>,
	Andrew Lunn <andrew@lunn.ch>,
	thomas.petazzoni@free-electrons.com, ymarkman@marvell.com,
	jason@lakedaemon.net, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Russell King - ARM Linux <linux@armlinux.org.uk>,
	kishon@ti.com, nadavh@marvell.com,
	miquel.raynal@free-electrons.com,
	gregory.clement@free-electrons.com, stefanc@marvell.com,
	mw@semihalf.com, davem@davemloft.net,
	linux-arm-kernel@lists.infradead.org,
	sebastian.hesselbarth@gmail.com
Subject: Re: [PATCH net-next 5/6] arm64: dts: marvell: mcbin: enable the fourth network interface
Date: Thu, 28 Dec 2017 19:27:39 +0100	[thread overview]
Message-ID: <20171228182739.GH2626@kwain> (raw)
In-Reply-To: <462da70b-ba7d-6299-3e21-b619d3c4c7e6@gmail.com>

Hi Florian,

On Thu, Dec 28, 2017 at 07:02:09AM -0800, Florian Fainelli wrote:
> On 12/28/2017 02:05 AM, Antoine Tenart wrote:
> > On Thu, Dec 28, 2017 at 08:46:23AM +0100, Andrew Lunn wrote:
> >> On Wed, Dec 27, 2017 at 10:24:01PM +0000, Russell King - ARM Linux wrote:
> >>> On Wed, Dec 27, 2017 at 11:14:45PM +0100, Antoine Tenart wrote:
> >>>>  
> >>>> +&cps_eth2 {
> >>>> +	/* CPS Lane 5 */
> >>>> +	status = "okay";
> >>>> +	phy-mode = "2500base-x";
> >>>> +	/* Generic PHY, providing serdes lanes */
> >>>> +	phys = <&cps_comphy5 2>;
> >>>> +};
> >>>> +
> >>>
> >>> This is wrong.  This lane is connected to a SFP cage which can support
> >>> more than just 2500base-X.  Tying it in this way to 2500base-X means
> >>> that this port does not support conenctions at 1000base-X, despite
> >>> that's one of the most popular and more standardised speeds.
> >>>
> >>
> >> I agree with Russell here. SFP modules are hot pluggable, and support
> >> a range of interface modes. You need to query what the SFP module is
> >> in order to know how to configure the SERDES interface. The phylink
> >> infrastructure does that for you.
> > 
> > Sure, I understand. We'll be able to support such interfaces only when
> > the phylink PPv2 support lands in.
> 
> Should we expect PHYLINK support to make it as the first patch in your
> v2 of this patch series, or is someone else doing that?

No, the phylink patch conflicts with Marcin's ACPI series and we agreed
to let him get his series merged first. And I will probably work on a
few other topics before having the chance to work on it. So it'll
probably be me doing that, but not right now.

This isn't an issue regarding the PPv2 and PHY patches of this series,
but yes we probably won't get the fourth network interface supported on
the mcbin during this release.

Thanks!
Antoine

-- 
Antoine Ténart, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com