While the previously featured Xperia Boot Menu was great for Sola, U, and GO users, this naturally caused Xperia P owners to feel a bit left out. Thankfully, XDA Senior Member percy_g2 has made progress in porting munjeni’s Xperia Boot Menu over to the final member of the device family, the Xperia P.
Just like munjeni’s original work, this solution relies on kexec to live boot the alternate kernel after the Xperia Boot Menu has been loaded. In order to use the modification, you need a tweaked kernel and recovery image. Luckily, both are provided in the thread’s OP, as well as instructions on how to get this running with CM 10.1.
If you wish to give this preview a shot, head over to the development thread and leave your feedback. Then once you’ve gotten the goods, head over to Senior Member NoobCoder‘s detailed guide on enabling the feature.