fn set_boot_time_us(&self, boot_time_us: u64) {
        // Please see `boot_time_us` for documentation on registers and peripherals
        // used for certain SOCs.

        let rtc_cntl = LP_AON::regs();

        let (l, h) = (rtc_cntl.store2(), rtc_cntl.store3());

        // https://github.com/espressif/esp-idf/blob/23e4823f17a8349b5e03536ff7653e3e584c9351/components/newlib/port/esp_time_impl.c#L102-L103
        l.write(|w| unsafe { w.bits((boot_time_us & 0xffffffff) as u32) });
        h.write(|w| unsafe { w.bits((boot_time_us >> 32) as u32) });
    }
Set the current value of the boot time registers in microseconds.
esp-hal/src/rtc_cntl/mod.rs