[U-Boot-Users] u-boot debugging boot with gdb and bdi2000 in lubbock(PXA255) board

Juan Antonio Garcia Redondo juan-antonio.garcia at nabla-designs.com
Thu Sep 4 17:46:16 CEST 2003

Wolfgang Denk wrote:

>In message <E19utSW-0000xx-00 at hall.mail.mindspring.net> you wrote:
>>I usually set TEXT_BASE=0 in board/lubbock/config.mk for debugging before 
>>start_armboot. No need to reflash. You should be able to reload symbols in 
>>gdb at offset 0, but for some reason I've never been able to get this to 
>>work correctly. So linking at 0 sets symbols for gdb correctly. Then you can 
>>use gdb in a normal manner.
>No need to recompile / relink. GDB will do  the  same  when  you  use
>"symbol-file"  to delte the current ymbol table and "add-symbol-file"
>to load the symbol file to the wanted target address (0x0).

Thanks Wolfgang and Kyle for your advice. Now, I can debug the boot 
process from the first instruction. Finally I've created two binaries: 
u-boot to execute  and u-boot.debug (with TEXTBASE=0x0), to debug the 
first part of boot process. When the boot process arrives to the 
start_armboot function, I discard the current symbol file(u-boot.debug)  
and load the new one(u-boot).

Now, I have a new (minor) problem. The execution order which shows the 
gdb seems to be wrong (I`ve stopeed at the start_armboot funcion and the 
lines which show the gdb are different of the real execution). I suppose 
that it is a compiler optimization problem. Anyone knows which are the 
suitable flags to use with the compiler to avoid this behaviour ?

    Juan Antonio

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