How to root and upgrade sony xperia U

[vinaysweetheart007]

Friend recently i buyed sony xperia U phone,iam entirely new to android rooting i have two doubts regarding my device :

1) How to update android ginger bread(2.3) to icecream sandwich(4.0)..?
recently i buyed sony xperia U phone on which android version ginger bread is installed...
i want to upgrade to icecream sandwich(4.0)...so can i know the complete procedure to upgrade my phn android software to iceream sandwich..
is all phones have a common procedure to upgrade..?

2) How to root my device..?
I wil be very thankfull to u if u can solve my problem bro.....

i searched this all over internet and on many sites but now of them were able to answer my questions..im completly hoping u can..
please do reply ur valuable advices and suggestions to this email..