On Wed, Nov 10, 2021 at 12:59:33PM +0100, Olivier Dautricourt wrote:

> I had the feeling that power profiles attributes such as
> totalTimeInaccuracy should be properties of the clock.
> In case of a simple BC or jbod, all the ports need to share the
> same inaccuracy.

If two ports have different HW, like one MAC and one PHY with
differing time stamping inaccuracy, then the values will be
different.

In addition, using a port attribute allows having the 2011/2017
flavors running on different ports.

> This way, we don't rely on users to forward the inaccuracy between ports
> with management tlvs.

This series treats the values as static.  There is no automatic
update.  The profile does not specify how to automatically calculate
the values.  On the contrary, it recommends a one time calibration
"during network engineering stage":

    Overall time inaccuracy should be calculated during network
    engineering stage based on device specifications and network
    design. All time inaccuracy values used in this calculation should
    be based on the manufacturer's specified device time inaccuracy
    values, along with the source time inaccuracy of the recognized
    standard time source.

> We also know that the totalTimeInaccuracy will
> always be the sum of other fields.

No, it is one or the other.  Either you have:

reserved1 = grandmasterTimeInaccuracy = 0, totalTimeInaccuracy != 0   2017 
flavor

or

grandmasterTimeInaccuracy != 0, networkTimeInaccuracy != 0            2011 
flavor

> So i don't think we should allow
> setting it through mgt.

ptpl4 makes consistent use of the management interface for values that
cannot be determined automatically.

Thanks,
Richard


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