[OLPC-devel] Re: wireless/libertas: miscellaneous fixes

[Dan Williams]

On Mon, 2006-06-26 at 16:31 -0600, Jordan Crouse wrote:
> On 26/06/06 16:58 -0500, Richard Smith wrote:
> > On 6/26/06, Jordan Crouse <jordan.crouse at amd.com> wrote:
> > 
> > >I build an initrd with wireless-tools, busybox and uclibc, and I only had
> > >9k left in the ROM when it was all said and done.  Granted, there is clean
> > >up to be had, but we're going to have to be prepared to pay the price for
> > >having all of these tools hanging about.
> > 
> > This seems really fat to me.  When I first started with linuxbios many
> > years ago I built a kexec setup that had to fit in 512k.  To make this
> > happen I had to customize (read hack) the pcmcia tools a bit.  I had
> > linux 2.4 + ornicco drivers + my really simple cardmgr/pcmcia tools +
> > iwconfig + dhclient + kexec all in there.  I had like 500 bytes left
> > over when it was done.
> 
> Well, remember that our kernel is about 600k since we have to
> build in support for NAND + USB + wireless, as well as the associated
> filesystems, and other sundry support.
> 
> The initrd itself is 320k. 
> 
> > How big are the wireless tools and busybox tools?
> 
> busybox is coming in at 205k.  I tried to stay pretty conservative in the
> configuration, but if we decide to go this route, then the
> original kexec-boot-loader binary will be re-implemented as a script, so
> we need to carry with us the usual script utilities, plus the usual system
> tools (mount, chroot, etc, etc).
> 
> All together the wireless tools are 164k.

iwconfig is 24k, libiw.so is 30k.  That's all you should really need.
And even that can be stripped, we can whip up a custom iwconfig pretty
fast that's likely 1/2 as small.  All iwconfig does is convert
command-line arguments to ioctl WEXT arguments.

Dan

> Finally the shared libraries are 320k - we could probably kill off some of
> those, and I'm still not sure if we're still at a point where static
> binaries are still a win, size wise.
> 
> > Since you are building an image that kexecs into another image is it
> > really necessary to have a whole lot of additional tools?  Its not
> > like you can do a whole lot if it fails other than re-flash a new
> > biosimage or kexec up whats on the usb drive.
> 
> I'll leave Marcelo to answer that more fully - I do know he is planning
> a method to reflash via the network, thus the wireless tools.  Last time
> I talked to him about it, I had trouble arguing in favor of the
> single-binary-that-does-everything approach.
> 
> Jordan
>