ks8695_gettimeoffset

Yegor Yefremov yegor_sub1 at visionsystems.de
Mon Dec 27 10:37:25 EST 2010


Am 20.12.2010 20:30, schrieb Russell King - ARM Linux:
> On Mon, Dec 20, 2010 at 01:09:47PM -0600, Dick Hollenbeck wrote:
>> >From userspace, printing the return values from a rapid looping
>> sequence of calls to
>>
>>    clock_gettime( CLOCK_MONOTONIC, &now );
>>
>> leads me to believe that kernel function ks8695_gettimeoffset() is
>> not worth anything.
> 
> That'll be because clock_gettime(CLOCK_MONOTONIC) doesn't use the old
> gettimeoffset() method to correct the returned time - none of the POSIX
> timers use the old gettimeoffset() stuff, only gettimeofday() does.
> 
> Platforms really should be using the clocksource/clockevents code
> where ever possible, rather than selecting ARCH_USES_GETTIMEOFFSET.
> 
> Does someone with a KS8695-based platform want to have a go at
> converting it over to clocksource/clockevents?

Is it possible at all to implement clocksource/clockevents for KS8695? As Dick and "Register Description" already said you cannot read the time register, so clocksource->read cannot be implemented to return ticks elapsed. Or do I see it wrong? 

Is there any documentation for clocksource/clockevents? 

Best regards,
Yegor



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