Re: [RFC PATCH 0/5] PTP: add support for Intel's TGPIO controller

From: Andrew Lunn
Date: Fri Jul 19 2019 - 09:20:50 EST


On Fri, Jul 19, 2019 at 10:35:14AM +0300, Felipe Balbi wrote:
>
> Hi,
>
> Andrew Lunn <andrew@xxxxxxx> 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.
> >
> > Hi Felipe
> >
> > Given the name TGPIO, can it also be used for plain old boring GPIO?
>
> not really, no. This is a misnomer, IMHO :-) We can only assert output
> pulses at specified intervals or capture a timestamp of an external
> signal.

Hi Felipe

So i guess Intel Marketing wants to call it a GPIO, but between
engineers can we give it a better name?

> > Also, is this always embedded into a SoC? Or could it actually be in a
> > discrete NIC?
>
> Technically, this could be done as a discrete, but it isn't. In any
> case, why does that matter? From a linux-point of view, we have a device
> driver either way.

I've seen a lot of i210 used with ARM SoCs. How necessary is the tsc
patch? Is there an architecture independent alternative?

Andrew