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Date:   Tue, 24 Aug 2021 19:08:14 -0700
From:   Richard Cochran <richardcochran@gmail.com>
To:     Harini Katakam <harinik@xilinx.com>
Cc:     Harini Katakam <harini.katakam@xilinx.com>,
        Nicolas Ferre <nicolas.ferre@microchip.com>,
        David Miller <davem@davemloft.net>,
        Claudiu Beznea <claudiu.beznea@microchip.com>,
        Andrei Pistirica <andrei.pistirica@microchip.com>,
        kuba@kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Michal Simek <michal.simek@xilinx.com>
Subject: Re: [RFC PATCH] net: macb: Process tx timestamp only on ptp packets
Message-ID: <20210825020814.GB25797@hoboy.vegasvil.org>
References: <20210824101238.21105-1-harini.katakam@xilinx.com>
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On Tue, Aug 24, 2021 at 08:59:20PM +0530, Harini Katakam wrote:
> Yes, there is no SW overhead because the  skb check ensures timestamp
> post processing is done only on requested packets. But the IP
> timestamps all packets
> because this is a register level setting, not per packet. That's the
> overhead I was referring to.

But the IP block time stamps the frames in silicon, no?

I don't see how that is "overhead" in any sense of the word.

Thanks,
Richard