Re: [Qemu-devel] (1) Xcode project?, (2) adding functionality

[Hetz Ben Hamo]

Hi Thomas,

On Apr 8, 2005 6:06 PM, Thomas Harte <address@hidden> wrote:
> I'm an 'experienced' emulator author and I have recently moved to Mac OS X. 
> I've never really been a UNIX user before, so I don't know GNU makefiles. In 
> my Microsoft past I always used some IDE or another to shield me from that 
> stuff, from RHide in the dim distant past to MSVC.

Well, you can use KDevelop, Eclipse or stuff like that, but you're
already moved to OS X, so any experience in Makefiles in OS X can help
you in the Linux/Unix world as well. the Make files in QEMU are not
that hard compared to the standard "configure" scripts found on many
packages (like GNOME or KDE) which they heavily use languages like M4
(which is a nightmare!). I think that if you'll dig a bit in the
makefiles, you'll find it's not that hard..
 
> I would like to modify Qemu in order to add support for a few devices not 
> currently emulated. I'm hoping this will be as simple as informing the 
> existing Qemu source of my new device by editing whatever array or data 
> structure controls what is visible on the PCI bus and directing it to pass 
> memory reads and writes within a certain range to my code. However I'm having 
> difficulty finding my way around.

Care to say which devices? maybe someone else on the list has
(silently) started to implement some things that you think to
implement..
 
> I'm becoming reasonably friendly with Apple's Xcode, so my first question is 
> whether anybody has bothered to compile an Xcode project for Qemu? Otherwise 
> I will have to seriously sit down with a guide to GNU makefiles in order to 
> make one myself and as I have no other general interest in them I was hoping 
> I might be able to skip this step. Otherwise, I guess it'll be good for me!

See above.
 
> My second question is whether anybody has written a quick start guide for 
> adding new modules to the Qemu source, or indeed any sort of documentation at 
> all that might help me get going?

I haven't seen any quick start documentation that someone written but:

1. QEMU code is not THAT big. It is seperated nicely to parts so you
can look around in the code for which parts you're looking for.
2. Have a look here: http://www.dad-answers.com/qemu/patches/ - there
are some patches which add few devicees, so you might want to see how
the authors added devices (I'm not sure that those patches will apply
cleanly today, though..)
3. Feel free to ask here in this list your questions..
4. Few developers are available sometimes on IRC (irc.freenode.net
channel: #qemu) - so you can ask there too..
 
> My vague aim is to attempt a 3dfx driver first (don't anybody get excited, 
> I'll probably fail) as the specs for that suggest it would be relatively easy 
> to get something that works a little going quite quickly, especially as it is 
> a pure rasterisation device. Give or take window sharing problems with the 
> existing Cirrus. Has anybody already started or attempted such a thing? I 
> checked out the archive and found some references implying nothing had been 
> done last July but that does leave an 8 month gap when someone may have done 
> something.

The Cirrus Logic was because it's drivers are available to almost any
OS, and as far as I heard from developers, it wasn't that hard to
implement. As for 3DFX, I think that 2D is still slow, so 3D going is
going to be extremly slow. However - it's your time and skills, so any
new stuff will be mostly welcome :)

Welcome aboard,
Hetz