Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Mon, 7 Jun 2021 14:09:24 +0100
From:   "Russell King (Oracle)" <linux@armlinux.org.uk>
To:     Steen Hegelund <steen.hegelund@microchip.com>
Cc:     "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>, Andrew Lunn <andrew@lunn.ch>,
        Microchip Linux Driver Support <UNGLinuxDriver@microchip.com>,
        Alexandre Belloni <alexandre.belloni@bootlin.com>,
        Madalin Bucur <madalin.bucur@oss.nxp.com>,
        Mark Einon <mark.einon@gmail.com>,
        Masahiro Yamada <masahiroy@kernel.org>,
        Arnd Bergmann <arnd@arndb.de>,
        Philipp Zabel <p.zabel@pengutronix.de>,
        Simon Horman <simon.horman@netronome.com>,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        Bjarni Jonasson <bjarni.jonasson@microchip.com>,
        Lars Povlsen <lars.povlsen@microchip.com>
Subject: Re: [PATCH net-next v3 03/10] net: sparx5: add hostmode with phylink
 support
Message-ID: <20210607130924.GE22278@shell.armlinux.org.uk>
References: <20210604085600.3014532-1-steen.hegelund@microchip.com>
 <20210604085600.3014532-4-steen.hegelund@microchip.com>
 <20210607091536.GA30436@shell.armlinux.org.uk>
 <9f4fad323e17c8ba6ebde728fcc99c87dd06fc75.camel@microchip.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <9f4fad323e17c8ba6ebde728fcc99c87dd06fc75.camel@microchip.com>
User-Agent: Mutt/1.10.1 (2018-07-13)
Sender: Russell King (Oracle) <linux@armlinux.org.uk>
Precedence: bulk

On Mon, Jun 07, 2021 at 02:45:01PM +0200, Steen Hegelund wrote:
> Hi Russell,
> 
> Thanks for your comments.
> 
> On Mon, 2021-06-07 at 10:15 +0100, Russell King (Oracle) wrote:
> > 3) I really don't get what's going on with setting the port mode to
> >    2500base-X and 1000base-X here when state->interface is 10GBASER.
> 
> The high speed interfaces (> 2.5G) do not support any in-band signalling, so the only way that e.g a
> 10G interface running at 2.5G will be able to link up with its partner is if both ends configure the
> speed manually via ethtool.

We really should not have drivers hacking around in this way. If we want
to operate in 2500base-x or 1000base-x, then that is what phylink should
be telling the MAC driver. The MAC driver should not be making these
decisions in its mac_config() callback. Doing so makes a joke of kernel
programming.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!