> With software, I can dump Flash0 which contains the actual firmware files. These
> files are encrypted and sig-checked though.
Right, and this is what Dullaron was alluding to. If MAME is going to emulate the PSP at all, we want to do it as low-level as possible.
However, even the couple MAMEdevs who have probably shipped a PSP title would have only interacted with the hardware via Sony's development libraries and OS calls, never talking to the low-level hardware itself.
As far as any of us are aware, all PSP "emulators", for their part, cut the system off at the knees and don't bother emulating it at a low level. Think of it like this - A MIPS R4000 chip always starts executing at a fixed address in memory: 0xBFC00000. There's always got to be something providing that initial startup code, either an internal ROM, or a microcontroller in the case of the N64, or whatever. By contrast - again, as far as any of us are aware - all PSP emulators just load the game executable directly into emulated memory, grovel into the Sony-documented executable header, and get the start address. Not exactly emulating the whole console, yeah?
So what we're looking for is any sort of documentation or dumps that are sufficiently low-level that they could be used to emulate a PSP from "hard" power-on.