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From: shawnguo@kernel.org (Shawn Guo)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] ARM: imx: Do L2 errata only if the L2 cache isn't enabled
Date: Thu, 18 Feb 2016 22:57:40 +0800	[thread overview]
Message-ID: <20160218145739.GC6756@tiger> (raw)
In-Reply-To: <56C03B0E.9000809@gmail.com>

On Sun, Feb 14, 2016 at 09:30:06AM +0100, Dirk Behme wrote:
> On 14.02.2016 09:18, Shawn Guo wrote:
> >On Fri, Feb 12, 2016 at 04:51:00PM +0100, Dirk Behme wrote:
> >>On 12.02.2016 15:16, Russell King - ARM Linux wrote:
> >>>On Fri, Feb 12, 2016 at 08:11:33AM +0100, Dirk Behme wrote:
> >>>>All the generic L2 cache handling code is encapsulated by a
> >>>>check if the L2 cache is enabled. If it's enabled already, the code
> >>>>is skipped.
> >>>>
> >>>>For the i.MX6 specific L2 cache handling we missed this check.
> >>>>Add it.
> >>>
> >>>What's the reasoning behind this?  The prefetch register is writable
> >>>while the L2 cache is enabled, unlike the auxiliary control register.
> >>
> >> From an internal log I have the following info:
> >>
> >>The write to the L2-Cache controller from non-secure world causes an
> >>imprecise
> >>external abort. If Linux runs from normal world the cache controller
> >>is already
> >>enabled and thus no configuration is needed by Linux.
> >
> >Dirk,
> >
> >Do you have a real use case of this, i.e. running Linux on i.MX6 in
> >non-secure world?
> 
> 
> Yes, in a scenario where one of the cores runs a RTOS.

Can you please reword the commit log to have the above non-secure world
user story mentioned in there?

Shawn

      reply	other threads:[~2016-02-18 14:57 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-12  7:11 [PATCH] ARM: imx: Do L2 errata only if the L2 cache isn't enabled Dirk Behme
2016-02-12 14:16 ` Russell King - ARM Linux
2016-02-12 15:51   ` Dirk Behme
2016-02-14  8:18     ` Shawn Guo
2016-02-14  8:30       ` Dirk Behme
2016-02-18 14:57         ` Shawn Guo [this message]

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