> -----Original Message-----
> From: [EMAIL PROTECTED] 
> [mailto:[EMAIL PROTECTED]
> ] On Behalf Of Amol Lad
> Sent: Tuesday, February 06, 2007 7:53 AM
> To: [email protected]
> Subject: Loading u-boot from u-boot
> 
> Hi,
> 
> I'd like to test uboot without burning the image in the flash 
> ? Can this be achieved ? Something like tftpboot  uboot image 
> from "tftpboot" u-boot command line and then "bootm" the image ? 
> 
> Any ideas ?


The biggest problem with doing this is that uboot will execute entirely
from DDR. What you have to remember is that one of the things that uboot
does is it configures the clocks and DDR controller. Configuring clocks
and the DDR controller is a bad thing to do when you are executing out
of DDR. If you try this uboot will probably crash at this point. 

There is one option and that is add some code to the platform.S file
(see board/davinci/ this is where the DDR controller and clocks are
initialised) that checks the address where the PC is currently pointing
and if the PC is pointing to a DDR location then skip the clock and DDR
init code as this has already been initialised. DDR is located at
address 0x8000000 and so the EMIF address space is lower, so you should
be able to simply test the MSB of the PC, if this is set then you are in
DDR and if not then you are in some other memory location. 

Cheers
Jon

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