From mboxrd@z Thu Jan  1 00:00:00 1970
From: will.deacon@arm.com (Will Deacon)
Date: Wed, 4 Apr 2012 12:07:17 +0100
Subject: oprofile and ARM A9 hardware counter
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To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

Hi Paul,

On Wed, Apr 04, 2012 at 01:00:53AM +0100, Paul Walmsley wrote:
> On Tue, 3 Apr 2012, Will Deacon wrote:
> 
> > I'll take JTAG for a whirl to see where we are. If anything looks wrong in
> > my dmesg, please shout (there are plenty of things in there that look like
> > they've gone awry).
> 
> Might be worth booting with initcall_debug on the kernel command line.  
> That will probably be easier than dealing with JTAG.

JTAG is unusable anyway because it requires a new MLO, which makes the
problem disappear.

Using initcall_debug I tracked the hang down to cti_unlock:

	val = __raw_readl(base + LOCKSTATUS);

causes the board to die, presumably because CoreSight isn't in a fit state
to be poked.

Will