This would need to be coded in kernel. However, lowering the minimum frequence would not mean we would have better battery life. I could go really long explaining this but i'll try to keep it basic. 1st, the energy used vs frequency is not linear. For example, 500Mhz would not use half the energy than 1Ghz. 2nd, This would either cause the kernel to have an higher load than 384Mhz, which would in fact increase the energy consumption or Bump the kernel to an higher frequency, which would make that frequency useless. In both case we are not winning any battery life.