[U-Boot-Users] Can U-boot Autodetect arch/ppcversusarch/powerpc from info in the uImage?

[Joakim Tjernlund <joakim.tjernlund@transmode.se>]

> -----Original Message-----
> From: Jerry Van Baren [mailto:gerald.vanbaren at ge.com] 
> Sent: den 13 december 2007 19:49
> To: Wolfgang Denk
> Cc: joakim.tjernlund at transmode.se; u-boot-users at lists.sourceforge.net
> Subject: Re: [U-Boot-Users] Can U-boot Autodetect 
> arch/ppcversusarch/powerpc from info in the uImage?
> 
> Wolfgang Denk wrote:
> > In message 
> <1197205927.937.51.camel@gentoo-jocke.transmode.se> you wrote:
> >> Made a new patch with Jerrys comments addressed. Also renamed
> >> DEFAULT_OF_TREE to CFG_OF_TREE. OK?
> > 
> > I still object against this modification.
> > 
> >> +#ifdef CFG_OF_TREE
> >> +	char	*of_flat_tree = CFG_OF_TREE;
> >> +#else
> >>  	char	*of_flat_tree = NULL;
> >> +#endif
> >>  	ulong	of_data = 0;
> >>  #endif
> > 
> > I hereby NAK this patch for 3 reasons:
> > 
> > 1) The patch does not solve a problem. Instead of hardwiring the
> >    address, you can just pass it as argument to the bootm command
> >    which seems more straightforward to me
> > 
> > 2) The patch causes confusion. Documented behaviour is that "bootm"
> >    with one or two arguments (kernel address, or kernel plus ramdisk
> >    addresses) will boot a non-OF enabled kernel. With this patch,
> >    "bootm" will behave different on systems where the 
> CFG_OF_TREE has
> >    been selected - which is usually not known to and cannot be
> >    checked by the end user, thus causing confusion.
> > 
> > 3) With the patch applied and CFG_OF_TREE defined, there is 
> no way to
> >    boot a non-OF kernel, thus breaking backward compatibility.
> > 
> > Best regards,
> > 
> > Wolfgang Denk
> 
> FWIIW, #2 and #3 are serious problems that I had not 
> considered when I 
> supported Jocke's proposed patch.  Sorry, Jocke, but I have 
> to side with 
> Wolfgang in light of those arguments.

Right and I havn't been able to come up with a solution to that either.
So I am looking at passing a $dtb to bootm.

I noticed that I could define dtb i HUSH only by
dtb=0x12345678
Is it possible to do that from within board code too?

If so I don't have to worry about deleting $dtb when downgrading,
because it will never be saved in the env.

 Jocke