[U-Boot] [PATCH] lib: time: Add microsecond timer

Simon Glass sjg at chromium.org
Wed Oct 16 16:40:54 UTC 2019


Hi Marek,

On Wed, 16 Oct 2019 at 02:55, Marek Vasut <marek.vasut at gmail.com> wrote:
>
> On 10/16/19 3:30 AM, Simon Glass wrote:
> > Hi Marek,
>
> Hi,
>
> > On Tue, 15 Oct 2019 at 14:43, Marek Vasut wrote:
> >>
> >> Add get_timer_us(), which is useful e.g. when we need higher
> >> precision timestamps.
> >
> > Can we use timer_get_us()? It seems confusing to have two.
>
> Nope, that one doesn't have the range (unsigned long vs. u64) and also
> doesn't behave the same way as old get_timer(). I wanted something which
> is similar, just for uS instead of mS.

Can you add comments to your patch to indicate what is going on any
why to use this?

Bootstage uses ulong which is enough for about an hour. How long is
U-Boot running?

If you are using differential times, presumably for timeouts, then
there seems to be little reason to need u64.

Regards,
Simon


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