http://hitmen.c02.at/html/psp_releases.html
source and precompiled module for 4.7. very basic right now (no stack variables, no emulation features) but atleast supports all Allegrex opcodes, including VFPU.
if you have experience with the sdk and know how to add the things mentioned in the todo file, get in touch... :=P
Allegrex CPU-Module for IDA
i have knocked up a quick and dirty cpu extension module aswell which you can use with existing IDA databases, so far it does nothing but add the 3 special allegrex opcodes... it might be useful if you are disassmbling code that uses those... also here: http://hitmen.c02.at/html/psp_releases.html