[U-Boot] u-boot boot process is broken, how do i recover?

[Albert ARIBAUD <albert.u.boot@aribaud.net>]

Hi JPT,

On Thu, 04 Apr 2013 12:21:43 +0200, JPT <j-p-t@gmx.net> wrote:

> Am 04.04.2013 11:17, schrieb Albert ARIBAUD:
> > Hi Thomas,
> >
> > On Thu, 4 Apr 2013 10:18:15 +0200, Thomas Petazzoni
> > <thomas.petazzoni@free-electrons.com> wrote:
> >
> >> On Marvell hardware, you can send a different U-Boot using the serial
> >> port, even if the on-flash U-Boot is broken. Have a look at
> >> tools/kwboot.c in the mainline U-Boot sources. It uses the serial port
> >> to send using the Xmodem protocol, a new U-Boot payload to the Kirkwood
> >> SoC.
> 
> mh, there is no kwb* (or kw?b*) neither in the netgear sources nor in 
> stock uboot-1.14

That's because kwb* is an official-U-Boot thing, and u-boot 1.1.4 is
way too old, and Netgear sources are based off 1.1.4.

> > Depends on the SoC. I am the proud owner of a Wireless Space which, due
> > its Kirkwood SoC's revision, cannot recover through UART even though
> > kirkwoods normally can. Not to mention my ED Mini V2, which has orion,
> > with no UART recovery at all.
> >
> > Also, UART recovery requires having a working U-boot image file. JPT, do
> > you have a working (pristine) U-Boot for your ReadyNAS, or can you get
> > one from Netgear?
> 
> I've got both, source and image.
> The first thing I did was reading the ROM to disk :)
> 1,5M 2013-02-10 20:18 mtd0.uboot.img
> 128K 2013-02-10 20:18 mtd1.uboot-env.img
> 6,0M 2013-02-10 20:19 mtd2.kernel.img
> 2,2M 2013-02-10 20:19 mtd3.initrd.img
>   89M 2013-02-10 20:17 mtd4.jffs2.img

Very wise of you.

> There is a UART_boot_file.zip included in the source:
> 32000  2008-06-05 19:35   bb11223344556677_boot.bin

Very convenient of Netgear. :)

> There are a lot of changes in the netgear uboot source.
> I don't know where to start.
> I cannot find your mail where you wrote about searching for something... o.O
> 
> Well, I think easiest would be to try loading the image through serial.
> Should I start with this?
> http://forum.doozan.com/read.php?3,4640,4640,quote=1

Since you seem to have a binary meant for UART booting, yes, you might
try sending it to the board; with any luck that'll allow you to inspect
and possibly revert your U-Boot environment into what it was before the
bricking. As to how... any serial app with Xmodem should work, I
presume. If the transfer starts, chances are the image will run
automatically.

> Thanks,
> 
> Jan

Amicalement,
-- 
Albert.