[OLPC-devel] just verified: 2306 + olpc + linux kernel works.

[Marcelo Tosatti]

Hi Ron!

On Thu, Jun 01, 2006 at 03:22:13PM -0600, Ronald G. Minnich wrote:
> Hi, I can not get this system with initrd and exec tool below about 480k.
> 
> It needs to now be really small: 384KB!
> 512 KB
> 64 KB controller (!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!)
> 32 KB linuxbios (I will try to shrink ...)
> 32 KB VSA
> ---------
> 384kb
> 
> This is *REALLY* small. However I am within 5k of being there.
> 
> OK, you're not going to like this, but ...I don't think, in 512kb, that we
> can afford an initrd. I don't think we can leave kernel mode until we have
> interacted a bit with the user, prompted for a root, mounted the root, and
> run /sbin/init from it.

Only if its the last option, I would say. Its much easier to maintain a
userspace program.

> 
> In other words, I think we're going to need to prompt in main() for
> options, and then do those options in main (kernel mode) and find a USB or
> FLASH root, and take it from there. I am going to look into this. I did it
> a few years ago for another linuxbios environment. Ugly, but it worked.
> 
> comments, brickbats, poison pen letters welcome.

Did I misunderstand what Ray said about 1MB SPI flash? 

"The SPI ROM is 1MB in A-test board, please combine the EC code in the
^^^^^^^^^^^^^^^^^^^
lowest (ie. beginning) address of flash."


In the meantime, few points which can be investigated:

- LZMA (you're using gzip compression, right?). 
- shrinkage patches in -tiny.
- creation of new shrinkage patches. There's a bunch of not needed stuff which 
can be removed. JFFS2 write support, for example. A lot of system calls and support 
code, too.
- -fwhole-program (any news David?)

You're using garbage collection, right?