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

[Simon Glass]

Hi Marek,

On Wed, 16 Oct 2019 at 10:44, Marek Vasut <marek.vasut at gmail.com> wrote:
>
> On 10/16/19 6:40 PM, Simon Glass wrote:
> > Hi Marek,
>
> Hi,
>
> > On Wed, 16 Oct 2019 at 02:55, Marek Vasut 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?
>
> It can run as long as anyone needs.
>
> > If you are using differential times, presumably for timeouts, then
> > there seems to be little reason to need u64.
>
> I use it for logging timestamps during profiling, e.g. of the EHCI driver.

Have you tried bootstage?

Regards,
Simon