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Date:   Wed, 17 Feb 2021 15:07:18 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Arnd Bergmann <arnd@kernel.org>
Cc:     Min Li <min.li.xe@renesas.com>,
        Derek Kiernan <derek.kiernan@xilinx.com>,
        Dragan Cvetic <dragan.cvetic@xilinx.com>,
        Arnd Bergmann <arnd@arndb.de>,
        gregkh <gregkh@linuxfoundation.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Networking <netdev@vger.kernel.org>,
        Richard Cochran <richardcochran@gmail.com>
Subject: Re: [PATCH net-next] misc: Add Renesas Synchronization Management
 Unit (SMU) support
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On Wed, 17 Feb 2021 22:30:14 +0100 Arnd Bergmann wrote:
> On Wed, Feb 17, 2021 at 9:20 PM Min Li <min.li.xe@renesas.com> wrote:
> > I attached the G.8273.2 document, where chapter 6 is about supporting physical layer
> > frequency. And combo mode is Renesas way to support this requirement. Other companies
> > may come up with different ways to support it.
> >
> > When EEC quality is below certain level, we would wanna turn off combo mode.  
> 
> Maybe this is something that could be handled inside of the device driver then?
> 
> If the driver can use the same algorithm that is in your user space software
> today, that would seem to be a nicer way to handle it than requiring a separate
> application.

Other points sound more time than networking, so no suggestions
from me, but on using PHC for L1 freq - that seems like a good 
fit for ethtool?