sec_out32(&rng->rtfreqmin, ent_delay >> 2);
        /* disable maximum frequency count */
        sec_out32(&rng->rtfreqmax, RTFRQMAX_DISABLE);
-       /* read the control register */
-       val = sec_in32(&rng->rtmctl);
        /*
         * select raw sampling in both entropy shifter
         * and statistical checker
         */
-       sec_setbits32(&val, RTMCTL_SAMP_MODE_RAW_ES_SC);
+       sec_setbits32(&rng->rtmctl, RTMCTL_SAMP_MODE_RAW_ES_SC);
        /* put RNG4 into run mode */
-       sec_clrbits32(&val, RTMCTL_PRGM);
-       /* write back the control register */
-       sec_out32(&rng->rtmctl, val);
+       sec_clrbits32(&rng->rtmctl, RTMCTL_PRGM);
 }
 
 static int rng_init(void)