Re: [PATCH] net: Bring up all interfaces before going interactive

[Sascha Hauer <s.hauer@pengutronix.de>]

On Mon, Sep 19, 2022 at 10:20:53AM -0700, Trent Piepho wrote:
> On Fri, Sep 16, 2022 at 6:16 AM Sascha Hauer <s.hauer@pengutronix.de> wrote:
> >
> > On Fri, Sep 16, 2022 at 02:49:42PM +0200, Sascha Hauer wrote:
> > > So far we only bring up network interfaces when we actually need them.
> > > This means we could be idling in the shell for long and once the user
> > > decides to do networking he has to wait for the link to be established.
> >
> > We could make the user experience even a bit better by doing this call
> > before waiting for the autoboot timeout which then speeds up netboot a
> > bit.
> 
> The Linux phy driver almost invariably does not bother to avoid
> resetting the network phy when not necessary.  So if network
> auto-negotiation is started in barebox, it will be reset and then
> restarted shortly after in Linux.  The link auto-negotiation impacts
> the LAN's spanning tree if that is in use.
> 
> So there is a drawback, besides the small added boot time to
> initialize the network hardware, to adding an unneeded network restart
> in Barebox in the case where interactive mode is not entered and
> network boot is not used.

So is this a vote to only do the autonegotiaton when going interactive
in barebox, or a vote to do autonegotiation only when the network is
being used in barebox?

Sascha

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