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Date:   Mon, 28 Jun 2021 17:23:29 +0300
From:   Vladimir Oltean <olteanv@gmail.com>
To:     Lukasz Majewski <lukma@denx.de>
Cc:     Andrew Lunn <andrew@lunn.ch>,
        "David S . Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Madalin Bucur <madalin.bucur@oss.nxp.com>,
        Nicolas Ferre <nicolas.ferre@microchip.com>,
        Joakim Zhang <qiangqing.zhang@nxp.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        netdev@vger.kernel.org, Arnd Bergmann <arnd@arndb.de>,
        Mark Einon <mark.einon@gmail.com>,
        NXP Linux Team <linux-imx@nxp.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [RFC 2/3] net: Provide switchdev driver for NXP's More Than IP
 L2 switch
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On Mon, Jun 28, 2021 at 04:13:14PM +0200, Lukasz Majewski wrote:
> > > > So before considering merging your changes, i would like to see a
> > > > usable binding.
> > > >
> > > > I also don't remember seeing support for STP. Without that, your
> > > > network has broadcast storm problems when there are loops. So i
> > > > would like to see the code needed to put ports into blocking,
> > > > listening, learning, and forwarding states.
> > > >
> > > > 	  Andrew
> >
> > I cannot stress enough how important it is for us to see STP support
> > and consequently the ndo_start_xmit procedure for switch ports.
>
> Ok.
>
> > Let me see if I understand correctly. When the switch is enabled, eth0
> > sends packets towards both physical switch ports, and eth1 sends
> > packets towards none, but eth0 handles the link state of switch port
> > 0, and eth1 handles the link state of switch port 1?
>
> Exactly, this is how FEC driver is utilized for this switch.

This is a much bigger problem than anything which has to do with code
organization. Linux does not have any sort of support for unmanaged
switches. Please try to find out if your switch is supposed to be able
to be managed (run control protocols on the CPU). If not, well, I don't
know what to suggest.