From mboxrd@z Thu Jan  1 00:00:00 1970
From: marex@denx.de (Marek Vasut)
Date: Tue, 25 Sep 2012 13:01:46 +0200
Subject: [PATCH] ARM: mx28: Skip OCOTP FEC MAC setup if in DT
In-Reply-To: <20120925051424.GB27291@S2101-09.ap.freescale.net>
References: <1348195214-26633-1-git-send-email-marex@denx.de>
 <20120925051424.GB27291@S2101-09.ap.freescale.net>
Message-ID: <201209251301.46486.marex@denx.de>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

Dear Shawn Guo,

> On Fri, Sep 21, 2012 at 04:40:14AM +0200, Marek Vasut wrote:
> > Currently, the kernel unconditionally adds "local-mac-address" and
> > "mac-address" properties under both FEC ethernet DT nodes in case
> > the update_fec_mac_prop() function is called. These properties are
> > loaded with MAC address compiled from vendors OUI and a per-device
> > NIC saved in OCOTP storage.
> > 
> > Some more advanced bootloaders do augment the DT passed to the kernel
> > by these properties already. In such case, it is wrong for kernel to
> > override these values.
> > 
> > Adjust the FEC MAC address loading so that in case the DT properties
> > are already present in the DT passed from the bootloader, skip the
> > loading from OCOTP altogether. If the DT properties are not present,
> > load them from OCOTP.
> > 
> > Note that the later case will lead to zeroed out MAC address if OCOTP
> > is not programmed. This will lead to FEC not working at all.
> > 
> > Signed-off-by: Marek Vasut <marex@denx.de>
> > Cc: Fabio Estevam <fabio.estevam@freescale.com>
> > Cc: Shawn Guo <shawn.guo@linaro.org>
> > ---
> > 
> >  arch/arm/mach-mxs/mach-mxs.c |    4 ++++
> >  1 file changed, 4 insertions(+)
> > 
> > diff --git a/arch/arm/mach-mxs/mach-mxs.c b/arch/arm/mach-mxs/mach-mxs.c
> > index 71d47f5..3f29a52 100644
> > --- a/arch/arm/mach-mxs/mach-mxs.c
> > +++ b/arch/arm/mach-mxs/mach-mxs.c
> > @@ -175,6 +175,10 @@ static void __init update_fec_mac_prop(enum mac_oui
> > oui)
> > 
> >  		np = of_find_compatible_node(from, NULL, "fsl,imx28-fec");
> >  		if (!np)
> >  		
> >  			return;
> > 
> > +
> > +		if (of_get_property(np, "local-mac-address", NULL))
> > +			continue;
> > +
> 
> The block should be put after "from" assignment below.

Can you please elaborate why would that be necessary?

Best regards,
Marek Vasut