[U-Boot-Users] [PATCH][FOR 1.3.4] 85xx: Don't move interrupt vector to low memory

[Jerry Van Baren]

Scott Wood wrote:
> On Wed, Aug 06, 2008 at 04:42:51PM +0200, Wolfgang Denk wrote:
>> In message <41F2F68F-34F5-4D3B-8AA1-294589B48033 at kernel.crashing.org> you wrote:
>>>> Oops? This is expected and normal behaviour. Did anybody complain
>>>> about this?
> 
> It's hit me before when I foolishly try to load something at address
> zero -- why do we put u-boot at the end of RAM, and put up with the
> relocation weirdness, if not to allow loading things at zero?
> 
>>> Real, any reason why?  I understand on classic PPC this might be the  
>>> case but I see no reason for it to be so on book-e parts.
>> Well, one reason might be to have identical code for all PPC systems ?
> 
> It's already 85xx-specific code.
> 
>>> Any they are.  I'm just removing a second relocation that is a hold  
>>> over from how 6xx PPC exception vectors work.
>> Not only 6xx. Actually all PPC.
> 
> No, not all PPC.  Book-E exceptions are different.
> 
> -Scott

One nice thing about not relocating the exception vectors to 0 is that 
it would allow us to recover from a failed bootm all the way up to the 
jump to linux (or whomever) rather than having to reset the board to 
recover from a failure late in the bootm sequence.

Unfortunately, it would be Book-E specific and probably not worth coding 
Yet Another Special Case in the already overcomplex bootm code.

Best regards,
gvb