RNG_REG_ERNG_OFFSET
writel(0, priv->base + RNG_REG_ERNG_OFFSET);
writel(ERNG_ENABLE, priv->base + RNG_REG_ERNG_OFFSET);
writel(0, priv->base + RNG_REG_ERNG_OFFSET);
ret = readl_poll_timeout(priv->base + RNG_REG_ERNG_OFFSET, status,