From mboxrd@z Thu Jan  1 00:00:00 1970
From: Richard Cochran <richardcochran@gmail.com>
Subject: Re: [RFC net-next 0/5] TSN: Add qdisc-based config interfaces for
 traffic shapers
Date: Fri, 1 Sep 2017 15:03:11 +0200
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References: <20170901012625.14838-1-vinicius.gomes@intel.com>
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To: Vinicius Costa Gomes <vinicius.gomes@intel.com>
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I happy to see this posted.  At first glance, it seems like a step in
the right direction.

On Thu, Aug 31, 2017 at 06:26:20PM -0700, Vinicius Costa Gomes wrote:
>  * Time-aware shaper (802.1Qbv):
...
>    S 0x01 300
>    S 0x03 500
> 
>    This means that there are two intervals, the first will have the gate
>    for traffic class 0 open for 300 nanoseconds, the second will have
>    both traffic classes open for 500 nanoseconds.

The i210 doesn't support this in HW, or does it?

>  * Frame Preemption (802.1Qbu):
> 
>    To control even further the latency, it may prove useful to signal which
>    traffic classes are marked as preemptable. For that, 'taprio' provides the
>    preemption command so you set each traffic class as preemptable or not:
> 
>    $ tc qdisc (...) \
>         preemption 0 1 1 1

Neither can the i210 preempt frames, or what am I missing?

The timing of this RFC is good, as I am just finishing up an RFC that
implements time-based transmit using the i210.  I'll try and get that
out ASAP.

Thanks,
Richard