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From:   Greentime Hu <green.hu@gmail.com>
Date:   Thu, 9 Nov 2017 15:24:08 +0800
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Subject: Re: [PATCH 20/31] nds32: L2 cache support
To:     Arnd Bergmann <arnd@arndb.de>
Cc:     Greentime <greentime@andestech.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-arch <linux-arch@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Jason Cooper <jason@lakedaemon.net>,
        Marc Zyngier <marc.zyngier@arm.com>,
        Rob Herring <robh+dt@kernel.org>,
        Networking <netdev@vger.kernel.org>,
        Vincent Chen <vincentc@andestech.com>, deanbo422@gmail.com
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2017-11-08 17:48 GMT+08:00 Arnd Bergmann <arnd@arndb.de>:
> On Wed, Nov 8, 2017 at 6:55 AM, Greentime Hu <green.hu@gmail.com> wrote:
>> From: Greentime Hu <greentime@andestech.com>
>>
>> Signed-off-by: Vincent Chen <vincentc@andestech.com>
>> Signed-off-by: Greentime Hu <greentime@andestech.com>
>
>> +
>> +/* This is defined for head.S to use due to device tree is not yet built. */
>> +#define L2CC_PA_BASE           0x90F00000
>
> This looks problematic, since it prevents you from using the same head.S for
> multiple SoCs that have different L2 controllers or that have them at different
> addresses.
>
> What does head.S actually do to the L2CC? Could the boot protocol require
> that to be done by the boot loader before entering the kernel instead?
>

Thanks.
It will disable and invalidate L2 cache. I think we can do these
things in bootloader.
I will refine it in the next version patch.

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