[U-Boot] [RFC] Review of U-Boot timer API

Wolfgang Denk
2011-05-25T12:59:03Z

Dear Graeme Russ,

In message <4DDCF926.1050904@gmail.com> you wrote:
>
> Many platforms have a hardware counter which is incremented without
> assistance from software - not by an ISR, nothing (I mentioned this before,
> but I can't track down the exact email) - THIS is the tick counter returned
> by get_ticks() which the prescaler uses to update the timer when you either:
>
> - Explicitly call get_timer()
> - Call the prescaler from an ISR
>
> The thing is, I have now highlighted that relying on interrupts to keep
> get_timer() working is a really bad idea - We have no way of stopping
> anyone from calling disable_interrupts() before using the timer

There may be code which doe snot call get_timer() for _long_ times.
And somebody disables interrupts. What's then?

Best regards,

Wolfgang Denk

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