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Date:   Thu, 27 Jul 2023 08:40:51 +0200
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Subject: Re: [PATCH v2] net: stmmac: correct MAC propagation delay
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To:     Richard Cochran <richardcochran@gmail.com>,
        Marc Kleine-Budde <mkl@pengutronix.de>
Cc:     kernel test robot <lkp@intel.com>,
        "David S. Miller" <davem@davemloft.net>,
        Russell King <linux@armlinux.org.uk>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        Eric Dumazet <edumazet@google.com>,
        Jose Abreu <joabreu@synopsys.com>,
        linux-arm-kernel@lists.infradead.org, kernel@pengutronix.de,
        Giuseppe Cavallaro <peppe.cavallaro@st.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        linux-stm32@st-md-mailman.stormreply.com,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
        patchwork-jzi@pengutronix.de
References: <20230719-stmmac_correct_mac_delay-v2-1-3366f38ee9a6@pengutronix.de>
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From:   Johannes Zink <j.zink@pengutronix.de>
In-Reply-To: <ZME88hOgNug+PFga@hoboy.vegasvil.org>
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Hi Richard,

On 7/26/23 17:34, Richard Cochran wrote:
> On Wed, Jul 26, 2023 at 08:04:37AM +0200, Marc Kleine-Budde wrote:
> 
>> At least the datasheet of the IP core tells to read the MAC delay from
>> the IP core (1), add the PHY delay (2) and the clock domain crossing
>> delay (3) and write it to the time stamp correction register.
> 
> That is great, until they change the data sheet.  Really, this happens.

I think I don't get your point here.

That's true for literally any register of any peripheral in a datasheet.
I think we can just stop doing driver development if we wait for a final
revision that is not changed any more. Datasheets change, and if they do we
update the driver.

Johannes


> 
> Thanks,
> Richard
> 
> 

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