Messages in this thread | | | Date | Fri, 4 Sep 2015 16:28:27 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH v3 1/4] Add correlated clocksource deriving system time from an auxiliary clocksource |
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On Fri, Sep 04, 2015 at 10:11:22AM +0200, Richard Cochran wrote: > On Thu, Sep 03, 2015 at 11:20:37PM +0000, Hall, Christopher S wrote: > > In addition to the network interface, ART will be used in the audio interface as well. > > We need to support the case where an audio co-processor will control the audio device. > > In this case, the get_ts() function supplied by the audio driver will be very slow > > (several milliseconds) and the result will be out of date by some fraction of that > > amount. > > Why does it take milliseconds to read one audio time stamp?
So what I suspect, but please correct me if I'm wrong Chris, is that a DSP will buffer and process audio signals, and only later wake up the main CPU.
So by the time the CPU is made aware of the data, it's 'old'.
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