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From: Andrew Lunn <andrew@lunn•ch>
To: Ran Shalit <ranshalit@gmail•com>
Cc: netdev@vger•kernel.org
Subject: Re: Q: force netif ON even when there is no real link ?
Date: Fri, 20 Apr 2018 14:05:16 +0200	[thread overview]
Message-ID: <20180420120516.GC20256@lunn.ch> (raw)
In-Reply-To: <CAJ2oMhJKOyFceuNwxVb4zPtF9Dm34s=JGfnp0AnP=c2zu7VWAA@mail.gmail.com>

On Fri, Apr 20, 2018 at 03:01:09PM +0300, Ran Shalit wrote:
> On Fri, Apr 20, 2018 at 2:55 PM, Andrew Lunn <andrew@lunn•ch> wrote:
> > On Fri, Apr 20, 2018 at 11:44:14AM +0300, Ran Shalit wrote:
> >> Hello,
> >>
> >> We configure external switch in u-boot.
> >> The configuration is through mdio (cpu is mac and switch is phy).
> >>
> >> But in Linux we rather not implement any communication in mdio to
> >> switch, but it means that we then don't have the information of link
> >> state.
> >>
> >> Is it possible to force in Linux (by default in startup) Ethernet
> >> connectivity (netif_carrier_on, netif_wake_queue) even if there is no
> >> information of real link state ?
> >
> > Hi Ran
> >
> > Use a fixed-phy.
> >
> 
> Hi Andrew,
> 
> I'll check about fixed phy,
> but in general, is it a problem to have always netif_carrier_on, even
> when there is no link ?

The link between the CPU and the switch should be up all the
time. That is the point of fixed-link.

    Andrew

  reply	other threads:[~2018-04-20 12:05 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-20  8:44 Q: force netif ON even when there is no real link ? Ran Shalit
2018-04-20 11:55 ` Andrew Lunn
2018-04-20 12:01   ` Ran Shalit
2018-04-20 12:05     ` Andrew Lunn [this message]
2018-04-20 12:14       ` Ran Shalit
2018-04-20 14:01         ` Ran Shalit
2018-04-20 22:04           ` Andrew Lunn

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