Re: [Gumstix-users] U-Boot and Etherstix

[Craig H. <cr...@gu...>]

On Jul 11, 2005, at 10:25 AM, Richard T. Stofer wrote:

> I would very much like to start booting using one of the network  
> schemes:
> bootp, tftp, nfs, etc.  The minicom, Kermit, flash copy, reboot  
> approach
> seems like the long way around.
>
> As a side issue, I would also like to mount the root file system  
> via NFS.
>
> Is the required driver for the etherstix included in the default U- 
> Boot
> configuration?

Yup.  bootp, dhcp, tftp, and even enough of nfs to read a bootfile  
over nfs all work great in u-boot.

> If it is not included is it doable?  I'm not asking for someone to  
> do it
> although suggestions are more than welcome.

See above :)

> What do I need to buy/build (prefer buy) to program a new version  
> of U-Boot
> into the flash?  I realize U-Boot can program itself but that  
> assumes that
> the new version works.  Not likely - if I have to write the include  
> the
> network driver!

You can do a two-u-boot shuffle.  Load new u-boot into u-boot in RAM  
(eg at 0xa2000000) then use the "go" command to execute u-boot from  
RAM instead of flash.  You'll now be running the new u-boot.  Test  
whatever you need to convince yourself it's OK, then reset.  You'll  
now be in old u-boot again.  Load new u-boot to RAM again (double  
check CRC), and then use old u-boot to write the new one from RAM to  
flash.  Now before cutting power, check the CRC of what you just  
wrote to flash, then cross fingers, and reboot :)

> FWIW, I have a bunch of JTAG cables from Digilent and Sparkfun.

That helps, in case you mess up the u-boot shuffle.  Hopefully you  
won't need them, but you can use them to recover if you do mess up  
and hose the first 2 sectors of flash.

C