rt-thread/components/drivers/cputime/Kconfig

config RT_USING_CPUTIME
    bool "Enable CPU time for high resolution clock counter"
    default n
    help
        When enable this option, the BSP should provide a rt_clock_cputime_ops
        for CPU time by:
        const static struct rt_clock_cputime_ops _ops = {...};
        clock_cpu_setops(&_ops);

        Then user can use high resolution clock counter with:

        ts1 = clock_cpu_gettime();
        ts2 = clock_cpu_gettime();

        /* and get the ms of delta tick with API: */
        ms_tick = clock_cpu_millisecond(t2 - t1);
        us_tick = clock_cpu_microsecond(t2 - t1);

if RT_USING_CPUTIME
    config RT_USING_CPUTIME_CORTEXM
        bool "Support Cortex-M CPU"
        default y
        depends on ARCH_ARM_CORTEX_M0 || ARCH_ARM_CORTEX_M3 || ARCH_ARM_CORTEX_M4 || ARCH_ARM_CORTEX_M7
        select PKG_USING_PERF_COUNTER
    config RT_USING_CPUTIME_RISCV
        bool "Use rdtime instructions for CPU time"
        default y
        depends on ARCH_RISCV64
        help
            Some RISCV64 MCU Use rdtime instructions read CPU time.
    config CPUTIME_TIMER_FREQ
        int "CPUTIME timer freq"
        default 0
endif