/*---------------------------------------------------------------------------*/
void
lpm_exit()
{
if((REG(SYS_CTRL_PMCTL) & SYS_CTRL_PMCTL_PM3) == SYS_CTRL_PMCTL_PM0) {
/* We either just exited PM0 or we were not sleeping in the first place.
* We don't need to do anything clever */
return;
}
LPM_STATS_ADD(REG(SYS_CTRL_PMCTL) & SYS_CTRL_PMCTL_PM3,
RTIMER_NOW() - sleep_enter_time);
/* Adjust the system clock, since it was not counting while we were sleeping
* We need to convert sleep duration from rtimer ticks to clock ticks and
* this will cost us some accuracy */
clock_adjust((clock_time_t)
((RTIMER_NOW() - sleep_enter_time) / RTIMER_CLOCK_TICK_RATIO));
/* Restore system clock to the 32 MHz XOSC */
select_32_mhz_xosc();
/* Restore PMCTL to PM0 for next pass */
REG(SYS_CTRL_PMCTL) = SYS_CTRL_PMCTL_PM0;
/* Remember IRQ energest for next pass */
ENERGEST_IRQ_SAVE(irq_energest);
ENERGEST_ON(ENERGEST_TYPE_CPU);
ENERGEST_OFF(ENERGEST_TYPE_LPM);
}
/*
* Routine to put is in PM0. We also need to do some housekeeping if the stats
* or the energest module is enabled
*/
static void
enter_pm0(void)
{
ENERGEST_OFF(ENERGEST_TYPE_CPU);
ENERGEST_ON(ENERGEST_TYPE_LPM);
/* We are only interested in IRQ energest while idle or in LPM */
ENERGEST_IRQ_RESTORE(irq_energest);
/*
* After PM0 we don't need to adjust the system clock. Thus, saving the time
* we enter Deep Sleep is only required if we are keeping stats.
*/
if(LPM_CONF_STATS) {
sleep_enter_time = RTIMER_NOW();
}
assert_wfi();
/* We reach here when the interrupt context that woke us up has returned */
LPM_STATS_ADD(0, RTIMER_NOW() - sleep_enter_time);
/* Remember IRQ energest for next pass */
ENERGEST_IRQ_SAVE(irq_energest);
ENERGEST_ON(ENERGEST_TYPE_CPU);
ENERGEST_OFF(ENERGEST_TYPE_LPM);
}
/*---------------------------------------------------------------------------*/
void
lpm_exit()
{
if((REG(SYS_CTRL_PMCTL) & SYS_CTRL_PMCTL_PM3) == SYS_CTRL_PMCTL_PM0) {
/* We either just exited PM0 or we were not sleeping in the first place.
* We don't need to do anything clever */
return;
}
/*
* When returning from PM1/2, the sleep timer value (used by RTIMER_NOW()) is
* not up-to-date until a positive edge on the 32-kHz clock has been detected
* after the system clock restarted. To ensure an updated value is read, wait
* for a positive transition on the 32-kHz clock by polling the
* SYS_CTRL_CLOCK_STA.SYNC_32K bit, before reading the sleep timer value.
*/
while(REG(SYS_CTRL_CLOCK_STA) & SYS_CTRL_CLOCK_STA_SYNC_32K);
while(!(REG(SYS_CTRL_CLOCK_STA) & SYS_CTRL_CLOCK_STA_SYNC_32K));
LPM_STATS_ADD(REG(SYS_CTRL_PMCTL) & SYS_CTRL_PMCTL_PM3,
RTIMER_NOW() - sleep_enter_time);
/* Adjust the system clock, since it was not counting while we were sleeping
* We need to convert sleep duration from rtimer ticks to clock ticks and
* this will cost us some accuracy */
clock_adjust((clock_time_t)
((RTIMER_NOW() - sleep_enter_time) / RTIMER_CLOCK_TICK_RATIO));
/* Restore system clock to the 32 MHz XOSC */
select_32_mhz_xosc();
/* Restore PMCTL to PM0 for next pass */
REG(SYS_CTRL_PMCTL) = SYS_CTRL_PMCTL_PM0;
/* Remember IRQ energest for next pass */
ENERGEST_IRQ_SAVE(irq_energest);
ENERGEST_ON(ENERGEST_TYPE_CPU);
ENERGEST_OFF(ENERGEST_TYPE_LPM);
}
/*
* Routine to put is in PM0. We also need to do some housekeeping if the stats
* or the energest module is enabled
*/
static void
enter_pm0(void)
{
ENERGEST_SWITCH(ENERGEST_TYPE_CPU, ENERGEST_TYPE_LPM);
/* We are only interested in IRQ energest while idle or in LPM */
ENERGEST_IRQ_RESTORE(irq_energest);
/* Remember the current time so we can keep stats when we wake up */
if(LPM_CONF_STATS) {
sleep_enter_time = RTIMER_NOW();
}
assert_wfi();
/* We reach here when the interrupt context that woke us up has returned */
LPM_STATS_ADD(0, RTIMER_NOW() - sleep_enter_time);
/* Remember IRQ energest for next pass */
ENERGEST_IRQ_SAVE(irq_energest);
ENERGEST_SWITCH(ENERGEST_TYPE_LPM, ENERGEST_TYPE_CPU);
}
