qpu_clock.py

#!/usr/bin/env python3

import time
from videocore.assembler import qpu, assemble
from videocore.driver import Driver

@qpu
def bench(asm, n):
    ldi(r0, int(n//4), set_flags=True)
    L.loop
    if 1:
        jzc(L.loop)
        iadd(r0, r0, -1, set_flags=True)
        nop()
        nop()
    exit(interrupt=True)

def main():

    n = 400e6 / 4

    with Driver() as drv:
        code = drv.program(bench, n)
        start = time.clock_gettime(time.CLOCK_MONOTONIC)
        drv.execute(n_threads=1, program=code)
        end = time.clock_gettime(time.CLOCK_MONOTONIC)
        print('%g [s], %g [insn/s]' % (end - start, n / (end - start)))
        print('Estimated clock: %g [MHz]' % (n / (end - start) * 4 * 1e-6))

if __name__ == '__main__':
    main()