CRT_CTRL2
u32 ctrl2 = readl(priv->base + CRT_CTRL2);
writel(ctrl2 | CRT_CTRL_DAC_EN, priv->base + CRT_CTRL2);
u32 ctrl2 = readl(priv->base + CRT_CTRL2);
writel(ctrl2 & ~CRT_CTRL_DAC_EN, priv->base + CRT_CTRL2);
writel(0, priv->base + CRT_CTRL2);