Initialize DBCR0 for PPC440 targets

[David Gibson]

On Tue, May 19, 2009 at 06:38:53PM +0530, srikanth krishnakar wrote:
> 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==0.

-- 
David Gibson			| I'll have my music baroque, and my code
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				| _way_ _around_!
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