[U-Boot-Users] Debugging U-Boot on 440GP

[Wolfgang Denk]

Dear brian,

in message <AKELKEJDICNMBGAOOBLACEOOCHAA.bpadalino at perigee.com> you wrote:
> 
>   - Wolfgang: The address of the PC of the 440GP is 0x00000700 or
> 0x00001400, but that is in my DDR memory.  I guess I am just missing what is
> really going on here.

Either you are trying to debug code _before_ relocation to RAM,  then
the exception vectors should still point to your boot image in flash;
or  you  are trying to debug code _after_ relocation to RAM, in which
case the exception vectors indeed point to RAM (as they should).

> I can single step my way through the display_options functions, and it says
> it's trying to write out the serial port (of which it isnt quite connected
> yet so I can't quite verify that yet), but if i set a break point at
> display_options, and let the CPU continue, it will never return to me.

Argh... you don't have a serial port attached? So do this first. IIRC
some 4xx ports even need HW handshake signals to allow any characters
go out of the console port.

> Am I not being patient enough?  Does debugging just take a significantly
> longer time?

It depends on how often you do this. The first time is always  a  bit
more difficult.

> For a preemptive question, once I get U-Boot up and running, I had a linux
> kernel running on the Ebony dev kit -- do you experts forsee any porting
> that will have to be done with that over to the custom platform?

Yes, of course.


Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at denx.de
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