Messages in this thread | | | From | <> | Subject | RE: [PATCH] net: lan743x_ptp: convert to ktime_get_clocktai_ts64 | Date | Wed, 15 Aug 2018 20:41:23 +0000 |
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> > > Question: this is the only ptp driver that sets the hardware time to > > > the current system time in TAI. Why does it do that? > > > > This is done when the driver starts up after reset. Otherwise the clock is off > by 48 years. > > It seemed to me that the system time was the most appropriate clock to > sync to. > > If my reasoning is incorrect, please enlighten me. > > I've never worked with PTP, but my understanding from looking at the other > drivers is that the time normally gets set either from another host through > the PTP protocol, or using clock_settime() from user space with the current > time.
Those methods will still work. But if it's not set by those methods, I thought the clock should at least be set once on driver startup to align with the system clock. After that, other methods are free to reset it again.
Bryan
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