[U-Boot] Getting started with uboot

[Thomas Heller <theller@ctypes.org>]

Where does uboot store the environment variables?

I have my tx25 board booting correctly from uboot when
entering interactive commands:

> U-Boot 2010.06 (Aug 02 2010 - 19:53:42)
> 
> CPU:   Freescale i.MX25 at 399 MHz
> 
> DRAM:  32 MiB
> NAND:  128 MiB
> *** Warning - bad CRC or NAND, using default environment
> 
> In:    serial
> Out:   serial
> Err:   serial
> Net:   FEC_MXC
> Hit any key to stop autoboot:  0
> => setenv bootcmd
> => nand read 0x80108000 0x02040000 0x00260000
> 
> NAND read: device 0 offset 0x2040000, size 0x260000
>  2490368 bytes read: OK
> =>
> 
> NAND read: device 0 offset 0x2040000, size 0x260000
>  2490368 bytes read: OK
> => bootm 0x80108000
> ## Booting kernel from Legacy Image at 80108000 ...
>    Image Name:   Linux-2.6.31
>    Image Type:   ARM Linux Kernel Image (uncompressed)
>    Data Size:    1517328 Bytes = 1.4 MiB
>    Load Address: 80008000
>    Entry Point:  80008000
>    Verifying Checksum ... OK
>    Loading Kernel Image ... OK
> OK
> 
> Starting kernel ...
> 
> Uncompressing Linux.................................................................................................... done, booting the kernel.

But when I call 'saveenv' then it doesn't boot any longer;
it seems that 'saveenv' overwrites parts of the root file system.

So, my question is: where does uboot save the environment?

-- 
Thanks,
Thomas