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Subject: Re: Question about DBCR0 initialization for 440
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Hollis Blanchard <hollisb@us.ibm.com>
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Date: Fri, 17 Apr 2009 21:04:47 +0200
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Cc: linuxppc-dev@ozlabs.org, John Linn <John.Linn@xilinx.com>,
	Tirumala Reddy Marri <tmarri@amcc.com>
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On Fri, 2009-04-17 at 13:07 -0500, Hollis Blanchard wrote:
> On Friday 17 April 2009 12:22:37 Josh Boyer wrote:
> > On Fri, Apr 17, 2009 at 11:46 AM, John Linn <John.Linn@xilinx.com> wrote:
> > > Josh, any thoughts on putting this into head_44x.S?
> > 
> > The code in the fsl file looks like the right solution.  I do have an
> > odd question though, in that it's hard for the
> > kernel to really know if something like a BDI is running.  Namely,
> > that config option doesn't cover RiscWatch in an obvious manner.
> 
> Yeah, setting DBCR0 would interfere with all JTAG probes. The ifdef meands you 
> can't support both a JTAG debugger and hardware breakpoints in the same 
> binary? Now that's an annoying restriction.

Might be worth checking if external debug is enabled, and override it
only if it's not.


Ben.