Subject: Re: [PATCH net-next 08/13] net: dsa: hellcreek: deny tc-taprio changes to per-tc max SDU

From: Kurt Kanzenbach <[email-masked]>
Date: Wed, 21 Sep 2022 13:23:24 +0200

On Thu Sep 15 2022, Vladimir Oltean wrote:
> On Thu, Sep 15, 2022 at 08:15:54AM +0200, Kurt Kanzenbach wrote:
>> > So the maxSDU hardware register tracks exactly the L2 payload size, like
>> > the software variable does, or does it include the Ethernet header size
>> > and/or FCS?
>> 
>> 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.

So, configured to 128 and 132 bytes (including VLAN Ethernet header) is
the maximum frame size which passes through.

Thanks,
Kurt