Re: Problem debugging ppc kernel with DDD/GDB/BDI2000 on a custom MPC8260 board

Dear Joao,

in message [ref] you wrote:

I am trying to boot the ppc kernel on a MPC8260 based custom board.

...

One of the doubts that I have is that when I look into the system.map file, it shows that the start address is at 0xc0000000 (as shown below)

c0000000 T _start

Yes, this is the correct kernel virtual address.

To the best of my knowledge the kernel image is not relocatable, so I am wondering if this could be my problem or just one of them ...
Should the map file be showing

00000000 T _start

No!!!

If so, where should I change the .text address so that that happens ?

Don't change anything!

I am also trying to debug the code from that address with gdb/BDI2000, but I am not getting very far.
Basically I can see the program counter incrementing when I single step, but I cannot see the source even though I am trying to load the symbol table at 0x00000000 with the  'add-symbol-file vmlinux 0x00000000' gdb command, after invoking gdb from the k
ernel base directory (where vmlinux is)

Just use the vmlinux file _without_ relocating  any  addresses.  Make
sure  to  enable  "MMU  XLAT"  and define "PTBASE" in your BDI config
file.


Best regards,

Wolfgang Denk

--
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd@denx.de
"If people are good only because they fear punishment, and  hope  for
reward, then we are a sorry lot indeed."            - Albert Einstein

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