Subject: Re: [RFC] New target 'cuImage' - compatibility uImage

From: Matthew McClintock <[email-masked]>
Date: Thu, 03 Aug 2006 15:20:38 -0500

On Thu, 2006-08-03 at 22:14 +0200, Wolfgang Denk wrote:
> Both approaches seem broken to me.
> 
> You should make sure that  your  bootstrap  code  comes  *after*  the
> kernel  image,  so  you  can  load  the  whole blob at address 0x0000
> (mkimage option "-a 0") while starting  it  at  the  bootstrap  entry
> point (mkimage option "-e <your_address>").

However, currently the zImage has an elfheader which will come before
the code. But, since we are making a new target we don't actually need
to preserve this. I like this idea. I will look into it further.

> 
> This way U-Boot will load (and if necessary  uncompress)  the  kernel
> image plus your attached bootstrap code to it's normal start address.
> Then  it starts your bootstrap code which can fixup DTB and then just
> start the kernel.
> 

We do not need to worry about this with cuImage because the kernel
section will not be compressed. If compression is desired it will be
done at the U-Boot level (were U-Boot would do the uncompressing).

> Please avoid any aditional memory copy. It's not necessary.
> 

Agreed.

-Matthew