[U-Boot] [RFC] Review of U-Boot timer API
Wolfgang Denk
wd at denx.de
Wed May 25 14:59:03 CEST 2011
Dear Graeme Russ,
In message <4DDCF926.1050904 at 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
--
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Your csh still thinks true is false. Write to your vendor today and
tell them that next year Configure ought to "rm /bin/csh" unless they
fix their blasted shell. :-)
- Larry Wall in Configure from the perl distribution
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