DIV_ROUND
div = DIV_ROUND((uint64_t)freq << 32, parent_freq);
return DIV_ROUND(freq, div1 * div2);
best_freq = DIV_ROUND(parent_freq, best_div1 * best_div2);
f = DIV_ROUND(parent_freq, div1 * div2);
div = DIV_ROUND(parent_freq, freq);