[U-Boot] Can I read env from RAM in uboot script?

[John Stile <john@stilen.com>]

On Mon, 2013-01-28 at 23:01 +0100, Jeroen Hofstee wrote:
> > On 01/28/2013 10:19 PM, John Stile wrote:
> >> On Sat, 2013-01-26 at 08:41 +0100, Wolfgang Denk wrote:
> >>> Dear John Stile,
> >>>
> >>> In message <1359165410.7974.114.camel@genx> you wrote:
> >>>> Is it possible to have uboot read it's environment from a RAM address,
> >>>> rather than NAND?
> >>>> OR
> >>>> Can uboot's scripting support load variables from a RAM address?
> >>> Yes, all this can be done.  And easily.  See for example the
> >>> "env import" command.
> >>>
> >> That is a great idea.
> >> What version of uboot introduced 'env import'?
> >> I'm stuck on u-boot-1.3.4.
> >> Is there a patch?
> >>
> > search the mailinglist, this is asking for a visit to
> > http://www.uboat.net/special/archiv/ or a response the
> > like. Try to upgrade if possible...
> 
> for completeness sake, Wolfgang will likely tell you it is museum material,
> since it is almost 5 years old. No idea what the site is about, just popped
> up with "u-boot museum" instead of Wolfgang's replies.
> 
I saw that.

I tried to update u-boot-1.3.4 to u-boot-2013.

I changed at91bootstrap's JUMP_ADDR from 0x23F00000 to 0x21F00000, as
advised by previous posts.

Now I am getting the wrong board type error from the kernel.
my board is an AT91SAM9G20EK_2MMC

I am having a hard time setting:
#define MACH_TYPE_AT91SAM9G20EK_2MMC   2288
insted of 
#define MACH_TYPE_AT91SAM9G20EK        1624

In had to change buildroot's .config from:
BR2_TARGET_UBOOT_BOARDNAME="at91sam9g20ek_2mmc_nandflash"
to
BR2_TARGET_UBOOT_BOARDNAME="at91sam9g20ek_nandflash"
whihch I suspect is the problem.

I'm trying to change the buildroots output/build/uboot-custom manually,
and rerun the build, but no luck yet.

My kernel is built with CONFIG_MACH_AT91SAM9G20EK_2MMC=y

So how do I force u-boot to agree?