ADE_OVLY_CTL
writel(0, base + ADE_OVLY_CTL);
val = readl(base + ADE_OVLY_CTL);
ade_update_bits(base + ADE_OVLY_CTL, CH_OVLY_SEL_OFST(ovly_ch),
ade_update_bits(base + ADE_OVLY_CTL, CH_OVLY_SEL_OFST(ovly_ch),