[U-Boot-Users] arm linux images with load address == entry point

[Uwe Kleine-König]

Hello Wolfgang,

> You download the image  to  an  arbitrary  address  which  should  be
> sufficiently  out  of  the  way  of  the [load_addr,load_addr+size of
> uncompressed kernel] area. The bootm will  (uncompress  &)  copy  the
> image to the load_addr, and jumpt to the entry point.
With the above command line (i.e. -C none) it will only copy it, not
uncompress.  But probably you meant that, as you put uncompress in
parenthesis.

> > For an image created with the above rule from the vanilla kernel, that
> > means, jump to the header (instead of the actual image at entry point +
> > 0x40).
> 
> No. The header will not be copied by U-Boot's "bootm" command.
Ah, OK, I see.  Then you may want to take the patch I'll send as a
follow up.
 
> > So I think the linux rule is wrong, or did I miss anything?
> 
> Yes. You talk about two addresses, but there are three.
> 
> > PS: Linux uses entry point == load address == 0 for PowerPC.  Didn't
> > look in the PowerPC version of bootm_linux, but maybe it has the same
> > problem?
> 
> It works the same in this respect. Note that I write *it works*.
> 
> > [1] For Linux this is not needed, because the decompressor (at least for
> > 2.6) is position independant.  But that's another topic.
> 
> Right - the decompressor  itself  is  not  needed,  as  it's  already
> included  in U-Boot. Adding it to the Kernel image just wastes memroy
> and time as it makes booting slower.
So you suggest to gzip the vmlinux image and use -C gzip?
 
Best regards,
Uwe

-- 
Uwe Kleine-König

http://www.google.com/search?q=12+mol+in+dozen