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From:   Felipe Balbi <felipe.balbi@linux.intel.com>
To:     Richard Cochran <richardcochran@gmail.com>
Cc:     netdev@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "H . Peter Anvin" <hpa@zytor.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org,
        "Christopher S . Hall" <christopher.s.hall@intel.com>
Subject: Re: [RFC PATCH 0/5] PTP: add support for Intel's TGPIO controller
In-Reply-To: <20190716164123.GB2125@localhost>
References: <20190716072038.8408-1-felipe.balbi@linux.intel.com> <20190716164123.GB2125@localhost>
Date:   Wed, 17 Jul 2019 09:52:55 +0300
Message-ID: <87ef2p2lvc.fsf@linux.intel.com>
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Hi,

Richard Cochran <richardcochran@gmail.com> writes:

> On Tue, Jul 16, 2019 at 10:20:33AM +0300, Felipe Balbi wrote:
>> TGPIO is a new IP which allows for time synchronization between systems
>> without any other means of synchronization such as PTP or NTP. The
>> driver is implemented as part of the PTP framework since its features
>> covered most of what this controller can do.
>
> Can you provide some background on this new HW?  Is the interface
> copper wires between chips?  Or is it perhaps coax between hosts?

It's just a pin, like a GPIO. So it would be a PCB trace, flat flex,
copper wire... Anything, really.

I think most of the usecases will involve devices somehow on the same
PCB, so a trace or flat flex would be more common. Perhaps Chris has a
better idea in mind? :-)

-- 
balbi