On Tue, Apr 08, 2008 at 11:01:53AM +0200, Laurent Pinchart wrote:
> On Tuesday 11 March 2008 18:24, Anton Vorontsov wrote:
> > GTM stands for General-purpose Timers Module and able to generate
> > timer{1,2,3,4} interrupts.
> >
> > There are several limitations in this support:
> > 1. Cascaded (32 bit) timers unimplemented (1-2, 3-4).
> > This is straightforward to implement when needed, two timers should
> > be marked as "requested" and configured as appropriate.
> > 2. Super-cascaded (64 bit) timers unimplemented (1-2-3-4).
> > This is also straightforward to implement when needed, all timers
> > should be marked as "requested" and configured as appropriate.
> >
> > Signed-off-by: Anton Vorontsov <[EMAIL PROTECTED]>
>
> [snip]
>
> > +void gtm_stop_timer_16(struct gtm_timer *tmr)
> > +{
> > + struct gtm *gtm = tmr->gtm;
> > + int num = tmr - >m->timers[0];
> > + unsigned long flags;
> > +
> > + spin_lock_irqsave(>m->lock, flags);
> > +
> > + setbits8(tmr->gtcfr, GTCFR_STP(num));
>
> Shouldn't we clear the timer events with
>
> out_be16(tmr->gtevr, 0xFFFF);
Yeah.
> here ? Otherwise the timer interrupt could still fire after the timer is
> stopped. This introduces a race condition in drivers that blindly re-arm the
> timer in the interrupt handler. I've been bitten by this while porting your
> FHCI USB driver to a CPM2 platform.
Thanks, will fix.
--
Anton Vorontsov
email: [EMAIL PROTECTED]
irc://irc.freenode.net/bd2
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