Qemu For Gp2x?

[Jaguarandine]

There was talk not long ago about porting QEMU to the GP2X. Obviously the reason you'd want to do this is to then run DOSEmu or WINE, which in turn would run DOS or Windows games. While this sounds like a great idea in theory, would it be fast enough to make it worthwhile? Assuming some games are playable, maybe overclocking can help with others? Interesting to think about, and it opens the door for more potential games..

 

[sand_man]

It probably would be to slow. But if someone actually wants to port it, there is no harm in trying.

 

[Robster]

It sounds like you're a little confused about what QEMU will give you. It will emulate an x86 PC, which is a good start, but you would also need an operating system inside QEMU and that's where the problems lie.

You could possibly run DOS inside QEMU and get some sort of operation, but you certainly won't run Windows inside QEMU on a GP2X! And to run Wine, you'd need to install x86 Linux, with X11, inside QEMU, and then run Wine on *it*. It would be a very cool thing if it worked (just to see it!) but really it's completely impractical.

The thing is, the GP2X already has a perfectly good OS. You don't really want to run a virtual OS inside QEMU on top of Linux, because that's too much overhead.

A more realistic goal would be to try and get a simple dos that can run 320x240 games. DosBox would be a good candidate, after all the recent stuff for emulating high-end CPUs and hardware was stripped out. GP2X could probably emulate a 20MHz 80286 quite well, but that's about it.

 

[Emu&Co]

1st: QEmu could help installing wine. QEmu has a nice feature called UserMode EMulation, which allows to start packages for other CPUs on ARM Linux.

2nd: QEmu Website says, that the emulated CPU is ~ 7 to 10 times slower than the Host CPU, so here should be ~ 20 Mhz possible, too.

3rd: QEMu is faster than DosBox, so this port would hardly get 20 MHz emulated speed.

 

[Jaguarandine]

It sounds like you're a little confused about what QEMU will give you. It will emulate an x86 PC, which is a good start, but you would also need an operating system inside QEMU and that's where the problems lie.

You could possibly run DOS inside QEMU and get some sort of operation, but you certainly won't run Windows inside QEMU on a GP2X! And to run Wine, you'd need to install x86 Linux, with X11, inside QEMU, and then run Wine on *it*. It would be a very cool thing if it worked (just to see it!) but really it's completely impractical.

The thing is, the GP2X already has a perfectly good OS. You don't really want to run a virtual OS inside QEMU on top of Linux, because that's too much overhead.

A more realistic goal would be to try and get a simple dos that can run 320x240 games. DosBox would be a good candidate, after all the recent stuff for emulating high-end CPUs and hardware was stripped out. GP2X could probably emulate a 20MHz 80286 quite well, but that's about it.

Thanks for that. It's kind of confusing for me looking at the things one would need to get it running. Which brings me to some other questions..

I was wondering if someone can clarify two things I read about it. I hope I don't look like too much of an idiot

1) (quote taken from qemu.com and Wikipedia) "User mode emulation (Linux host only). In this mode, QEMU can launch Linux processes compiled for one CPU on another CPU."
I figured that this meant as long as the host computer runs Linux regardless of CPU architecture, it can run things designed for Linux on other architectures. This seems to be more efficient than full system emulation, which I assume, is what most emulators like ZSNES or DrMDx do.


2) (quote taken from Wikipedia) "Wine and Dosemu are the main targets for QEMU."
Assuming you have Linux on an x86 machine, you wouldn't need QEMU as you could run these programs directly. Also, I've heard about an attempt to combine QEMU and WINE for PowerPC CPUs called Darwine. The intention overall must be to get decent speed from WINE with current software.

I hope that made sense.

Edit: I see someone partly answered my post as I was constructing it. I'll leave it up unchanged anyway.

 

[Jaguarandine]

Just been thinking the last few days of some issues that there might be for getting this to work. One of them is sound emulation. I'm pretty sure the gp2x would have to emulate sound (sound blaster 16 at least) because it doesn't have a sound processor per se. Not sure how much this would slow down the CPUs. Another is the greater demands newer x86 CPUs (i.e., 386 to Pentium) might have on emulation.

Now, in a perfect world (start rant based on assumptions ), with QEMU and DOSEMU/WINE in place, both CPUs being used to full potential and running at 266 MHz each (533 MHz), you might be able to emulate an x86 at 50-105 MHz, which is just good enough for games like Blood and Warcraft 2. Possibly, even faster with higher overclocking and/or more RAM. A pipe dream atm, but nice to think about nonetheless..

 

[Emu&Co]

This is all theoretical. First we would need someone who builds it for GP2X. Then we can see what will work and what not.