On 07.12.2021 19:10:45, Uwe Kleine-König wrote: > Some hardware units capture a timestamp for the counted event. To > increase precision add a variant of counter_push_event() that allows > passing this timestamp. > > Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx> > --- > Hello, > > the difficulty is that the captured timer value is in a unit different > from the one provided by ktime_get_ns(). So maybe some helper functions > will be needed to convert the local timer value to a ktime timestamp? > > So usage would be something like: > > ktime_now = ktime_get_ns(); > local_now = readl(CNT); > local_event = readl(...); > > ktime_event = ktime_now - (local_now - local_event) * somefactor >> someshift; You can use cyclecounter/timecounter for this. Marc -- Pengutronix e.K. | Marc Kleine-Budde | Embedded Linux | https://www.pengutronix.de | Vertretung West/Dortmund | Phone: +49-231-2826-924 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
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