[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Sun, 5 May 2019 07:41:19 +0200
From: Oleksij Rempel <o.rempel@...gutronix.de>
To: Chuanhong Guo <gch981213@...il.com>
Cc: Andrew Lunn <andrew@...n.ch>, Paul Burton <paul.burton@...s.com>,
Ralf Baechle <ralf@...ux-mips.org>,
James Hogan <jhogan@...nel.org>,
Rob Herring <robh+dt@...nel.org>,
Jay Cliburn <jcliburn@...il.com>,
Chris Snook <chris.snook@...il.com>,
"David S. Miller" <davem@...emloft.net>,
Mark Rutland <mark.rutland@....com>,
Pengutronix Kernel Team <kernel@...gutronix.de>,
linux-mips@...r.kernel.org,
open list <linux-kernel@...r.kernel.org>,
devicetree@...r.kernel.org, John Crispin <john@...ozen.org>,
Felix Fietkau <nbd@....name>, netdev@...r.kernel.org
Subject: Re: [PATCH v3 3/3] net: ethernet: add ag71xx driver
On Sat, May 04, 2019 at 11:40:53PM +0800, Chuanhong Guo wrote:
> Hi!
>
> On Mon, Apr 22, 2019 at 9:28 PM Andrew Lunn <andrew@...n.ch> wrote:
> > [...]
> > > + /*
> > > + * On most (all?) Atheros/QCA SoCs dual eth interfaces are not equal.
> > > + *
> > > + * That is to say eth0 can not work independently. It only works
> > > + * when eth1 is working.
> > > + */
> >
> > Please could you explain that some more? Is there just one MDIO bus
> > shared by two ethernet controllers? If so, it would be better to have
> > the MDIO bus controller as a separate driver.
>
> mdio registers exists on both ethernet blocks. And due to how reset
> works on this ethernet IP, it's hard to split it into a separated
> driver. (Only asserting both eth and mdio resets together will reset
> everything including register values.)
> The reason why gmac1 should be brought up first is that on some chips,
> mdio on gmac0 connects to nothing and phy used by gmac0 is on mdio bus
> of gmac1.
It could be implemented as mfd device. Not sure if it is worth it.
Pro/contra argumentation is welcome.
--
Pengutronix e.K. | |
Industrial Linux Solutions | http://www.pengutronix.de/ |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
Powered by blists - more mailing lists