MAX_BIT
tb_cycle = (tb_cycle << (MAX_BIT - value + 1));
pw20_idle |= ((MAX_BIT - *value) << PWRMGTCR0_PW20_ENT_SHIFT);
if (entry_bit > MAX_BIT)
tb_cycle = (tb_cycle << (MAX_BIT - value + 1));
altivec_idle |= ((MAX_BIT - *value) << PWRMGTCR0_AV_IDLE_CNT_SHIFT);
if (entry_bit > MAX_BIT)