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To:     Kurt Kanzenbach <kurt@linutronix.de>
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Subject: Re: [PATCH net-next 08/13] net: dsa: hellcreek: deny tc-taprio
 changes to per-tc max SDU
Thread-Topic: [PATCH net-next 08/13] net: dsa: hellcreek: deny tc-taprio
 changes to per-tc max SDU
Thread-Index: AQHYyE9hWKLuwg2RcUaJgx4+STifDq3fOt+AgAAHiYCAAMIyAIAAX/qA
Date:   Thu, 15 Sep 2022 11:59:26 +0000
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On Thu, Sep 15, 2022 at 08:15:54AM +0200, Kurt Kanzenbach wrote:
> > So the maxSDU hardware register tracks exactly the L2 payload size, lik=
e
> > the software variable does, or does it include the Ethernet header size
> > and/or FCS?
>=20
> This is something I'm not sure about. I'll ask the HW engineer when he's
> back from vacation.

You can also probably figure this out by limiting the max-sdu to a value
like 200 and seeing what frame sizes pass through.=