Subject: Re: [PATCH 2/6] net: ethernet: ti: cpts: add support for ext rftclk
 selection
To: Richard Cochran <richardcochran@gmail.com>
References: <20161128230428.6872-1-grygorii.strashko@ti.com>
 <20161128230428.6872-3-grygorii.strashko@ti.com>
 <20161130095632.GC28680@localhost.localdomain>
CC: "David S. Miller" <davem@davemloft.net>, <netdev@vger.kernel.org>,
        Mugunthan V N <mugunthanvnm@ti.com>, Sekhar Nori <nsekhar@ti.com>,
        <linux-kernel@vger.kernel.org>, <linux-omap@vger.kernel.org>,
        Rob Herring <robh+dt@kernel.org>, <devicetree@vger.kernel.org>,
        Murali Karicheri <m-karicheri2@ti.com>, Wingman Kwok <w-kwok2@ti.com>
From: Grygorii Strashko <grygorii.strashko@ti.com>
Message-ID: <bf207ac4-0f9f-d4a7-14ac-704d93fb7764@ti.com>
Date: Wed, 30 Nov 2016 11:35:06 -0600
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On 11/30/2016 03:56 AM, Richard Cochran wrote:
> On Mon, Nov 28, 2016 at 05:04:24PM -0600, Grygorii Strashko wrote:
>> Some CPTS instances, which can be found on KeyStone 2 1/10G Ethernet
>> Switch Subsystems, can control an external multiplexer that selects
>> one of up to 32 clocks for time sync reference (RFTCLK). This feature
>> can be configured through CPTS_RFTCLK_SEL register (offset: x08).
>>
>> Hence, introduce optional DT cpts_rftclk_sel poperty wich, if present,
>> will specify CPTS reference clock. The cpts_rftclk_sel should be
>> omitted in DT if HW doesn't support this feature. The external fixed
>> rate clocks can be defined in board files as "fixed-clock".
> 
> Can't you implement this using the clock tree, rather than an ad-hoc
> DT property?
> 

I've thought about this, but decided to move forward with this impl
 which is pretty simple. I will try.


-- 
regards,
-grygorii