Move wireless firmware to OFW device tree?

[Dan Williams]

On Sat, 2007-02-03 at 21:23 -1000, Mitch Bradley wrote:
> 
> Marcelo Tosatti wrote:
> > (moving to olpc-devel)
> >
> > On Sat, Jan 27, 2007 at 02:53:07AM +0100, Arnd Bergmann wrote:
> >
> >   
> >> Since we now have an Open Firmware based system, the libertas firmware
> >> could be stored inside of the firmware device tree. The most significant
> >> advantage of that is that you can boot with the libertas driver enabled
> >> before mounting the file system.
> >>
> >> Another advantage is that if we get a forth implementation of the driver
> >> that can do PXE boot, the open firmware can use the same copy of the
> >> libertas firmware blob as Linux.
> >>     
> >
> > Yeah, it does make sense to do it. However, we would have to think about
> > the firmware upgrade process. This is sorted out now since its currently
> > packed as an RPM on-flash.
> >
> > My knowledge one the OFW device tree is rather limited, can you store
> > binary blob's such as firmware in it? Are any other architectures doing
> > that already?
> >   
> The fundamental data type for device tree properties is "array of 
> bytes", so it could export a firmware blob easily.
> > BTW, how's the OF driver implementation work going?
> >   
> Lilian has it associating with several access points in her 
> neighborhood, and pinging to her laptop, so we are getting pretty 
> close.  We need to discuss what kinds of authentication we want to 
> support and various other network management issues.

This is quite an interesting question.  If, from OFW, we do WEP, we need
to allow key entry in some manner, and in at least hex format.  I'm not
sure we can do WPA at all, because even WPA-PSK requires a supplicant.
Maybe somebody has done an OFW supplicant already?

Here's what we need to do:  figure out exactly what things we want to
enable with wireless-in-OFW, and build out from those cases.  We
shouldn't be just adding a generic wireless config screen to OFW; we
should be targetting the specific use-cases we wish to enable and
building the bits to support them.

Dan