[PATCH v2 3/4] Implement clockevents driver for powerpc
Sergei Shtylyov
sshtylyov at ru.mvista.com
Tue Oct 16 04:33:46 EST 2007
Hello, I wrote:
>>@@ -797,6 +796,53 @@ void __init clocksource_init(void)
>> clock->name, clock->mult, clock->shift);
>> }
>>+static int decrementer_set_next_event(unsigned long evt,
>>+ struct clock_event_device *dev)
>>+{
>>+ set_dec(evt);
> I'd use (evt - 1) since the interrupt gets generated at 0xffffffff count,
> not 0 (on classic CPUs). With you removing of the code that compensated for
> the errors, they will accumulate. And no, this wouldn't be enough anyway,
> since on 40x and Book E you'll need to set it for evt anyway, since the
> interrupt happens at 0 count...
What that means is that the off-by-one-clock drift is introduced for
classic CPUs (not 40x or Book E which interrupt at 0). And this has dealt
with months ago in the clockevent driver in the -rt patch. So much for my
efforts...
> NAK the patch.
It's too late for NAKs -- I should've given these patches more attention
(yet I was in hospital for 1.5 months).
WBR, Sergei
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