From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dinh Nguyen <dinguyen@opensource.altera.com>
Subject: Re: SoCFPGA ethernet broken
Date: Fri, 16 Oct 2015 14:10:02 -0500
Message-ID: <alpine.DEB.2.02.1510161407570.22838@linux-builds1>
References: <562005AD.8020903@opensource.altera.com> <56200BD7.8020505@gmail.com> <56200E15.9080603@caviumnetworks.com> <56201158.8040806@opensource.altera.com> <56201AE7.2020103@gmail.com> <alpine.DEB.2.02.1510152102280.22844@linux-builds1>
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Cc: Andrew Lunn <andrew@lunn.ch>,
	Florian Fainelli <f.fainelli@gmail.com>,
	"David S. Miller" <davem@davemloft.net>, <david.daney@cavium.com>,
	<netdev@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
To: David Daney <ddaney@caviumnetworks.com>
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <56212A09.5080206@caviumnetworks.com>
Sender: linux-kernel-owner@vger.kernel.org
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On Fri, 16 Oct 2015, David Daney wrote:

> On 10/16/2015 08:56 AM, Andrew Lunn wrote:
> > > So I think I'll move to inspect what Florian had suggested, and that was
> > > to look
> > > at:
> > > drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c::stmmac_mdio_register
> > 
> > I have a suspicion. If you look at the phy driver it does:
> > 
> > static int ksz9021_config_init(struct phy_device *phydev)
> > {
> >          const struct device *dev = &phydev->dev;
> >          const struct device_node *of_node = dev->of_node;
> > 
> >          if (!of_node && dev->parent->of_node)
> >                  of_node = dev->parent->of_node;
> > 
> 
> Maybe we need to walk up the hierarchy.
> 
> Perhaps something like:
> 
> const struct device *dev_walker;
> 
> dev_walker = &phydev->dev;
> do {
>    of_node = dev_walker->of_node;
>    dev_walker = dev_walker->parent;
> } while (!of_node && dev_walker);
> 

The above code seems to have fixed the issue.

> An alternative would be to assign the bus the same of_node as the bus parent.
> 
> If either approach works, you can add:
>  Acked-by: David Daney <david.daney@cavium.com>
> 
> to the patch that implements it.
> 
> > 
> > In your case, you don't have a phy node in your device tree, so of_node
> > is NULL. So it looks in the parent device.
> > 
> >      phylib: Make PHYs children of their MDIO bus, not the bus' parent.
> > 
> > changed what the parent is. It is now the mdio device. Before, i
> > suspect it was the MAC. Hence it found your properties in the MAC
> > node.
> > 
> > What i think you might want to do is change this code. Rather than
> > look a dev->parent->of_node; you might want
> > phydev->attached_dev->dev->of_node.
> > 
> > This assumes the phy has been attached to the MAC. I've no idea of the
> > ordering, so maybe it has not been attached yet?
> > 
> > dp83867.c has similar code. However quick grep did not find any
> > mainline users with properties in the MAC node. If that is true, i
> > would suggest removing the code looking in the parent for that phy
> > driver.
> > 
> > 	Andrew
> > 
> 
> 

BR,
Dinh