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From: Kumar Gala <galak@kernel.crashing.org>
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Subject: Re: [RFC] 4xx hardware watchpoint support
Date: Wed, 23 Jul 2008 07:51:13 -0500
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On Jul 22, 2008, at 8:47 PM, Luis Machado wrote:

> Hi,
>
>> That, or adding a small function to move the bits to the appropriate
>> registers (set_dbcr or set_dac_events).
>>
>>> Do you think it's worth to support this facility on 405's  
>>> processors? If
>>> so, i'll gladly work on a solution to it.
>>
>> I would think so.  There's really no difference from a userspace
>> perspective, so gdb watchpoints could be valuable there too.  I'll
>> leave it up to you though.
>
> As the 440 support is ready and the 405 needs additional tweaking  
> due to
> the use of DBCR1 instead of DBCR0 and due to a different position  
> scheme
> of the DAC1R/DAC1W flags inside DBCR1, i'd say we should include this
> code and handle the 405 case later.
>
> We might have to handle it anyway if we're going to pursue the  
> hardware
> breakpoint interface work in the future.
>
> I've fixed some formatting problems. Tested on a 440 Taishan board and
> on a PPC970. Both worked as they should. Ok?

I'd like to test this on some Freescale Book-e parts.  Is there a gdb  
patch or some user space ptrace test you have?

- k