[Prism54-users] Re: [Prism54-devel] Prism54 development update

[Denis Vlasenko]

On Wednesday 07 September 2005 22:30, Jean-Baptiste Note wrote:
> Hey Maxi, Denis,
> 
> I've got some questions for you... 
> 
> As you may already have noticed, the documentation i'm doing for the
> firmware dump is for my eyes and understanding only. 
> 
> Have you got any ideas / tools / methodology that i could use and
> imitate so that the comments would be usefull to *others* ?

Well, I think the steps are:

1) make a arm .S file which, when compiled, gives you _exactly_ same
   image as reverse-engineered one.

2) heavily comment it (can be done by many people in parallel).
   Give symbolic names to labels, variables etc...
   (evolution: b 1234 -> b lbl_1234 -> b disable_tx)

3) when you feel it's more or less understood, try some
   more invasive changes (which change length of fw image and/or
   offsets of code/data).

4) if (3) runs without crashes, well, it's mostly done.

> Do you know Maxi for instance how the Madwifi hal people operate ?
> 
> I'd very much like you thoughts on this.
> 
> As for the clean room implementation : that's a little bit how we're
> doing today, as Sebastien does the coding / hardware hacking and i'm
> doing the firmware reading. But there's not yet enough people on board
> that we can ensure the clean room concept ; furthermore i don't know
> what copyrighted code i can gather from the ASM, but surely not so
> much ;)

I'm at "need to try that armulator thing" stage now.
--
vda