diff --git a/drivers/char/hw_random/bcm2835-rng.c b/drivers/char/hw_random/bcm2835-rng.c
index 6767d965c36c..186fe2fcfeac 100644
--- a/drivers/char/hw_random/bcm2835-rng.c
+++ b/drivers/char/hw_random/bcm2835-rng.c
@@ -105,8 +105,10 @@ static int bcm2835_rng_init(struct hwrng *rng)
 	}
 
 	/* set warm-up count & enable */
-	rng_writel(priv, RNG_WARMUP_COUNT, RNG_STATUS);
-	rng_writel(priv, RNG_RBGEN, RNG_CTRL);
+	if (!(rng_readl(priv, RNG_CTRL) & RNG_RBGEN)) {
+		rng_writel(priv, RNG_WARMUP_COUNT, RNG_STATUS);
+		rng_writel(priv, RNG_RBGEN, RNG_CTRL);
+	}
 
 	return ret;
 }