Subject: Re: [PATCH 1/1] Calculate the monotonic clock from the timespec clock
 to generate PPS elapsed real-time event value and stores the result into
 /sys/class/pps/pps0/assert_elapsed.
To:     Alexander Komrakov <alexander.komrakov@broadcom.com>,
        linux-kernel@vger.kernel.org
References: <20211118032217.244985-1-alexander.komrakov@broadcom.com>
 <20211118032217.244985-2-alexander.komrakov@broadcom.com>
From:   Rodolfo Giometti <giometti@enneenne.com>
Message-ID: <a2dd9fa7-c6d2-d234-7652-53014672fe0a@enneenne.com>
Date:   Fri, 26 Nov 2021 11:49:25 +0100
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On 18/11/21 04:22, Alexander Komrakov wrote:
> From: alexkom <alexander.komrakov@broadcom.com>
> 
> Because we have requirements to make sure the delta between standard time, say the GPS Time, and elapsedRealtime < 1 millisecond, regular linux clock timestamp is not enough for our use case.
> The pin PPS will generate elapsedRealtime event at 1 sec boundary which is an exact value of the monotonic clock from the kernel PPS driver (/sys/class/pps/pps0/assert_elapsed).
> 
> Whenever AP receives this pulse, kernel's pps driver timestamp this elapsedRealtime event and let this time available via sysfs node (/sys/class/pps/pps0/assert_elapsed).
> 
> Signed-off-by: alexkom <alexander.komrakov@broadcom.com>

Acked-by: Rodolfo Giometti <giometti@enneenne.com>

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