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Date: Mon, 22 Mar 2010 08:57:39 +0100
From: Daniel Mack <daniel@caiaq.de>
To: Haojian Zhuang <haojian.zhuang@gmail.com>
Cc: Eric Miao <eric.y.miao@gmail.com>,
       linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
       linux-kernel@vger.kernel.org
Subject: Re: PXA3xx internal SRAM
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References: <20100321124739.GG30801@buzzloop.caiaq.de>
 <771cded01003211747n29be55a3p7608578ff1744f51@mail.gmail.com>
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On Sun, Mar 21, 2010 at 08:47:22PM -0400, Haojian Zhuang wrote:
> On Sun, Mar 21, 2010 at 8:47 AM, Daniel Mack <daniel@caiaq.de> wrote:
> > The pxa3xx series features a comparatively big and fast internal SRAM of
> > 256KB which is currently unused by the Linux kernel except for a 4-byte
> > return vector from suspend.
> >
> > I wonder what this could be used for. Is there any kind of cache that
> > would be worth putting there to speed up things for example?
> > And could the uncompressor probably benfit from that?
> >
> > Daniel
> 
> The size of internal SRAM isn't always 256KB. It could be 128KB, 256KB
> or 702KB. In marvell BSP, there's a memory management driver (aka IMM)
> to handle internal SRAM. So driver or user application could make use
> of it. And one part of internal SRAM is reserved for low power idle
> mode. But both of these two features aren't pushed into community yet.

Ok. I was more thinking about any kernel specific kind of cache that has
a fix size of 128kb or 256kb and which is consulted regularily. But I
don't know which kind of cache that could be.

As that's not neccessarily ARM-related, I copied LKML. Maybe anyone has
an idea.

Thanks,
Daniel