embox

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/**
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 * @file
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 * @brief
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 *
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 * @author  Anton Kozlov
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 * @date    30.10.2014
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 */
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#include <stdint.h>
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#include <sys/types.h>
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#include <hal/clock.h>
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#include <hal/cpu_idle.h>
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#include <kernel/time/clock_source.h>
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#include <kernel/time/time.h>
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#include <kernel/time/timer.h>
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void arch_cpu_idle(void) {
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	extern const struct clock_source *cs_jiffies;
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	struct clock_source *cs;
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	uint64_t next_event_cycles;
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	clock_t next_event_ticks;
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	clock_t sleep_ticks;
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	if (!cs_jiffies) {
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		return;
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	}
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	cs = (struct clock_source *)cs_jiffies;
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	if (timer_strat_get_next_event(&next_event_ticks) != 0) {
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		/* Sleep as long as possible */
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		next_event_ticks = UINT32_MAX;
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	}
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	else {
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		next_event_ticks = next_event_ticks - clock_sys_ticks();
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	}
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	next_event_cycles = clock_source_ticks2cycles(cs, next_event_ticks);
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	if (next_event_cycles > cs->counter_device->mask) {
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		next_event_cycles = cs->counter_device->mask;
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	}
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	clock_source_set_oneshot(cs);
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	clock_source_set_next_event(cs, next_event_cycles);
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	__asm__ __volatile__("WFI");
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	sleep_ticks = clock_source_cycles2ticks(cs, clock_source_get_cycles(cs));
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	jiffies_update(sleep_ticks);
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	clock_source_set_periodic(cs, cs->event_device->event_hz);
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}
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