Hello Grant,

Is there any conclusion of the below discussion:

http://www.nabble.com/Question-about-DBCR0-initialization-for-440-td2304904=
4.html

Xilinx target (virtex5) hangs (while running GDBServer & KGDB) without
the DBCR0 initialization.

Can you please comment on this ?


Thanks,
-Srikanth

On Wed, May 20, 2009 at 11:20 AM, srikanth krishnakar
[off-list ref] wrote:

Hi David,

I am not sure how the IDM behaves on few of PPC440 targets which don't
have boot loaders. I have a reference for your question:

http://www.nabble.com/Question-about-DBCR0-initialization-for-440-td23049=

044.html

Without this fix (given patch) I am facing problems with GDB, and
further target hangs while running gdbserver !

Thanks,
Srikanth

On Wed, May 20, 2009 at 5:23 AM, David Gibson
[off-list ref] wrote:

quoted

On Tue, May 19, 2009 at 06:38:53PM +0530, srikanth krishnakar wrote:

quoted

Hi,

kernel- 2.6.29
Debug technique: KGDB

The PowerPC kernel does not initialize the PPC440 DBCR0 register. This
prevents the use of software breakpoints in case of internal debug
mode. Looking into head_fsl_booke.S for initialization of DBCR0 is
used by boot-loaders.
It seems head_44x.S lacks this step of DBCR0 register initialization.
So fixing this with initializing the DBCR0 register as shown below :

Subject: [PATCH] powerpc: 44x: Initialize DBCR0 for targets not having
bootloader

The kernel does not initialize the PPC440 DBCR0 register.
This prevents (among other things) the use of software
breakpoints with GDB. The boot loaders probably do initialize
this but few targets run without a boot loader

Um.. how does this prevent the use of software breakpoints with gdb?
The trap instructions still work with IDM=3D=3D0.

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 baroque, and my code

quoted

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_other_

quoted

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quoted

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--
"The Good You Do, The Best You GET"

Regards
Srikanth Krishnakar
**********************

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"The Good You Do, The Best You GET"

Regards
Srikanth Krishnakar
**********************