From mboxrd@z Thu Jan  1 00:00:00 1970
From: Aneesh V <aneesh@ti.com>
Date: Thu, 17 Mar 2011 19:04:37 +0530
Subject: [U-Boot] Working on u-boot on panda board.
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To: u-boot@lists.denx.de

Hi Gilles,

On Thursday 17 March 2011 06:13 PM, Gilles Chanteperdrix wrote:
>
> Hi,
>
> I would like to make some changes to u-boot on pandaboard. Sometimes in
> the past, in u-boot, I could "loadb" a new u-boot binary, then "go" to
> it, and the new version of u-boot would start. This was far from
> perfect, but it made testing small changes possible. This also works
> with the version of u-boot provided on the pandaboard community site.
>
> The magic which made this possible was in the "start.S" file, I see that
> the code changed, but there still seems to be a relocation (somewhat
> more complicated, since it handles ELF relocations), so it seems it
> should work.
>
> So my question is: is this "loadb+go" method still supposed to be
> working, and only broken, somehow, on pandaboard? Or is it no longer
> supposed to be working?

Couple of things you might want to consider.
* According to the new relocation scheme u-boot should start running
from the address that it is linked to. You must load it to
CONFIG_SYS_TEXT_BASE
* Data cache enabled in U-Boot could be a problem. You will end up
having cache coherency issues unless you flush the caches after loadb.
Better keep them disabled using CONFIG_SYS_NO_DCACHE

>
> Regards.
>