From mboxrd@z Thu Jan  1 00:00:00 1970
From: shawn.guo@freescale.com (Shawn Guo)
Date: Wed, 18 Jun 2014 20:39:08 +0800
Subject: [PATCH] ARM: save/restore diagnostic register on ARMv7
 suspend/resume
In-Reply-To: <20140618104009.GH32699@arm.com>
References: <1403081398-32116-1-git-send-email-shawn.guo@freescale.com>
 <20140618104009.GH32699@arm.com>
Message-ID: <20140618123906.GI8860@dragon>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Wed, Jun 18, 2014 at 11:40:09AM +0100, Will Deacon wrote:
> On Wed, Jun 18, 2014 at 09:49:58AM +0100, Shawn Guo wrote:
> > The CP15 diagnostic register holds ARM errata bits on ARMv7, so it
> > needs to be saved/restored on suspend/resume.  Otherwise, the
> > effectiveness of errata workaround gets lost together with diagnostic
> > register bit across suspend/resume cycle.
> 
> This should be conditional on Cortex-A9, since this register is certainly
> not architected.

Ah, yes.  In that case, I should probably handle it at platform level to
avoid messing up generic ARMv7 suspend/resume routines.

Shawn