Message-ID: <56E33F64.2000208@caviumnetworks.com>
Date: Fri, 11 Mar 2016 13:57:56 -0800
From: David Daney <ddaney@caviumnetworks.com>
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To: Andrew Lunn <andrew@lunn.ch>
CC: David Daney <ddaney.cavm@gmail.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Mark Rutland <mark.rutland@arm.com>, Robert Richter <rric@kernel.org>,
        Pawel Moll <pawel.moll@arm.com>,
        Ian Campbell <ijc+devicetree@hellion.org.uk>, <netdev@vger.kernel.org>,
        David Daney <david.daney@cavium.com>, <linux-kernel@vger.kernel.org>,
        Rob Herring <robh+dt@kernel.org>, Kumar Gala <galak@codeaurora.org>,
        Sunil Goutham <sgoutham@cavium.com>,
        Radha Mohan Chintakuntla <rchintakuntla@cavium.com>,
        "David S. Miller" <davem@davemloft.net>,
        <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH 1/3] net: thunderx: Cleanup PHY probing code.
References: <1457714822-5754-1-git-send-email-ddaney.cavm@gmail.com> <1457714822-5754-2-git-send-email-ddaney.cavm@gmail.com> <20160311173125.GI3153@lunn.ch> <56E30332.7060003@caviumnetworks.com> <20160311180030.GB19277@lunn.ch> <56E30DDF.5040506@caviumnetworks.com> <20160311190627.GC19277@lunn.ch> <56E31E7A.6080905@gmail.com> <56E330E4.9090800@gmail.com> <20160311213516.GE19277@lunn.ch>
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On 03/11/2016 01:35 PM, Andrew Lunn wrote:
[...]
> How usable is the hardware without a PHY driver?

The hardware has always in the past, still does, and probably always 
will work fine without a PHY driver.  Link up/down are correctly handled.

> Is a better solution
> that your write a very minimal PHY driver?

No.  Nothing would be gained.

All we are trying to do, is allow for loading of 1G PHY drivers via the 
-EPROBE_DEFER mechanism while continuing to allow the 10G and 40G ports 
to function without a PHY driver.

Specifically, we are *not* attempting to solve the problem of 
re-architecting the kernel phy_device infrastructure so that it would be 
possible to write a Cortina PHYs driver.  Nor are we proposing that a 
Cortina PHY driver be written that would fit into the current 
infrastructure.

To this end, I still think the current patch takes the best approach.

Thanks,
David Daney