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    //! RISC-V timer-related functionality

    use crate::config::CLOCK_FREQ;
    use crate::sbi::set_timer;
    use riscv::register::time;

    const TICKS_PER_SEC: usize = 100;
    const MSEC_PER_SEC: usize = 1000;

    pub fn get_time() -> usize {
        time::read()
    }

    /// get current time in microseconds
    pub fn get_time_ms() -> usize {
        time::read() / (CLOCK_FREQ / MSEC_PER_SEC)
    }

    /// set the next timer interrupt
    pub fn set_next_trigger() {
        set_timer(get_time() + CLOCK_FREQ / TICKS_PER_SEC);
    }