Re: [Gumstix-users] uboot testing

[Dave H. <dhy...@gm...>]

Hi James,

On 6/6/07, James Wilson <ji...@ho...> wrote:
> Can you use u-boot to load and test a customised uboot?
> What would be the best way to test a custom build u-boot leaving the
> original in its flash space protected?

Yes. You would load the test u-boot from some other location (you can
read files from the JFFS2 filesystem, or you can load it over serial,
TFTP, from MMC, or CF.

Now - which address to use is interesting.

On the connex, and on the 1.1.4 version of u-boot on the verdex,
u-boot is loaded to A3F00000. On the verdex for u-boot-1.2.0, it's
loaded to 5c000000 (which appears to 256k of internal RAM).

I performed the following test on my verdex, with the following two
files in my /root directory on the gumstix:

1321-u-boot.bin (which is 1.1.4)
1352-u-boot.bin (which is 1.2.0)

Runnng 1.1.4 (which executes from A3F00000), I tried the following:

fsload a2000000 1321-u-boot.bin
go a2000000

which worked fine.

fsload a2000000 /root/1352-u-boot.bin
go a2000000

failed, however

fsload 5c000000 /root/1352-u-boot.bin
go 5c000000

worked fine.

While running the 1352 version of u-boot (which executes from 5c000000)

fsloading to a2000000 works fine.

u-boot checks the address it's currently running at and if it's not at
the correct address, it relocates itself and runs from the relocated
address.

So, you don't want to load to the address that the current u-boot is
runnung from, and the only address I could use with u-boot-1.1.4 to
load 1.2.0 was 5c000000

-- 
Dave Hylands
Vancouver, BC, Canada
http://www.DaveHylands.com/