When tickless is available, all existing devices can handle much
higher timing precision than 10ms. A 10kHz default seems acceptable
without introducing too much range limitation (rollover for a signed
time delta will happen at 2.5 days). Leave the 100 Hz default in
place for ticked configurations, as those are going to be special
purpose usages where the user probably actually cares about interrupt
rate.
Note that the defaulting logic interacts with an obscure trick:
setting the tick rate to zero would indicate "no clock exists" to the
configuration (some platforms use this to drop code from the build).
But now that becomes a kconfig cycle, so to break it we expose
CONFIG_SYS_CLOCK_EXISTS as an app-defined tunable and not a derived
value from the tick rate. Only one test actually did this.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
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