Dunno if you know, but some time ago (2005/08/12, to be exact), Matan Gillon ported Bochs to the PSP:
As I already posted in <a href=http://www.reactos.org/forum/viewtopic.php?p=28882#28882>this ROS’ forum 3ad it would be interesting to have a port of Haiku on it.
I think it’s Windows running in Bochs, running on Linux. The only true port here being Linux. Windows95 is likely to run at small fraction of the speed of the PSP device, with most of the CPU time used by Bochs.
A port of Haiku could be interesting, but for this class of devices I’d say it’s wiser to spend time on the GP2X, which is open to experimentation, unlike the PSP.
I agree, the gp2x is very interesting.
The PSP can’t run ordinary Linux kernels because it doesn’t have an MMU. There are two MMU-less variants of Linux, one of which, ELKS, is for PC AT era hardware (ie 20+ years old) and is now effectively obsolete, and another, uClinux, which is for micro-controllers. There is a port of uClinux to the PSP in progress, but the results so far are not very exciting.
What was linked above is a port of Bochs to the PSP’s firmware, so that you can run either Linux or Windows on top of the Bochs emulator. You can see in the instructions it explains how to download a 10Mbyte mini-distribution of Linux and configure Bochs to run it. As with the uClinux port, this is purely showing off and doesn’t have any identifiable purpose yet, not least because as you realised it’s extremely slow.
Since Haiku, like regular Linux kernels, makes use of an MMU, it can’t be ported to the PSP.
I stand corrected. It just didn’t compute, seeing Bochs on the bare metal. Impressive.
A port of Haiku is possible. The lack of mmu means someone will have to rework the VM to handle that case and write stubs, but if Linux can do it, why not Haiku 
Also, as Haiku uses mostly load_image in place of fork+exec, it will likely ease porting, because fork is the main problem when not having an mmu.
Still it’s not exactly the main focus.