Struct LiteXAlarm

pub struct LiteXAlarm<'t, 'c, R: LiteXSoCRegisterConfiguration, F: Frequency> { /* private fields */ }

LiteX alarm implementation, based on LiteXTimer and LiteXTimerUptime

LiteX does not have an Alarm compatible hardware peripheral, so an Alarm is emulated using a repeatedly set LiteXTimer, comparing the current time against the LiteXTimerUptime (which is also exposed as Time::now.

Implementations

impl<'t, 'c, R: LiteXSoCRegisterConfiguration, F: Frequency> LiteXAlarm<'t, 'c, R, F>

pub fn new( uptime: &'t LiteXTimerUptime<'t, R, F>, timer: &'t LiteXTimer<'t, R, F>, ) -> LiteXAlarm<'t, 'c, R, F>

pub fn initialize(&'t self)

Initialize the LiteXAlarm

This will register itself as a client for the underlying LiteXTimer.

Trait Implementations

impl<'c, R: LiteXSoCRegisterConfiguration, F: Frequency> Alarm<'c> for LiteXAlarm<'_, 'c, R, F>

fn set_alarm_client(&self, client: &'c dyn AlarmClient)

Specify the callback for when the counter reaches the alarm value. If there was a previously installed callback this call replaces it.

fn set_alarm(&self, reference: Self::Ticks, dt: Self::Ticks)

Specify when the callback should be called and enable it. The callback will be enqueued when Time::now() == reference + dt. The callback itself may not run exactly at this time, due to delays. However, it it assured to execute after reference + dt: it can be delayed but will never fire early. The method takes reference and dt rather than a single value denoting the counter value so it can distinguish between alarms which have very recently already passed and those in the far far future (see #1651).

fn get_alarm(&self) -> Self::Ticks

Return the current alarm value. This is undefined at boot and otherwise returns now + dt from the last call to set_alarm.

fn is_armed(&self) -> bool

Returns whether the alarm is currently armed. Note that this does not reliably indicate whether there will be a future callback: it is possible that the alarm has triggered (and disarmed) and a callback is pending and has not been called yet. In this case it possible for is_armed to return false yet to receive a callback.

fn disarm(&self) -> Result<(), ErrorCode>

Disable the alarm and stop it from firing in the future. Valid Result<(), ErrorCode> codes are:

fn minimum_dt(&self) -> Self::Ticks

Return the minimum dt value that is supported. Any dt smaller than this will automatically be increased to this minimum value.

impl<'t, R: LiteXSoCRegisterConfiguration, F: Frequency> Time for LiteXAlarm<'t, '_, R, F>

type Frequency = F

The number of ticks per second

type Ticks = <LiteXTimerUptime<'t, R, F> as Time>::Ticks

The width of a time value

fn now(&self) -> Self::Ticks

Returns a timestamp. Depending on the implementation of Time, this could represent either a static timestamp or a sample of a counter; if an implementation relies on it being constant or changing it should use Timestamp or Counter.

impl<R: LiteXSoCRegisterConfiguration, F: Frequency> TimerClient for LiteXAlarm<'_, '_, R, F>

fn timer(&self)