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Message-ID: <8d6898730707102243t60861fdar147f052501c31958@mail.gmail.com>
Date: Wed, 11 Jul 2007 11:13:20 +0530
From: "Nobin Mathew" <nobin.mathew@gmail.com>
To: "Manu Abraham" <abraham.manu@gmail.com>
Subject: Re: Reading a physical memory location
Cc: "vraghavan3@mail.gatech.edu" <vraghavan3@mail.gatech.edu>,
       linux-kernel@vger.kernel.org
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Which is your platform ?

Which processor?

If you want to use physical address directly, then disable MMU. That
is not possible in linux.

Nobin

On 7/11/07, Manu Abraham <abraham.manu@gmail.com> wrote:
> On 7/10/07, vraghavan3@mail.gatech.edu <vraghavan3@mail.gatech.edu> wrote:
> >
> > Thanks for the quick reply. But I was wondering as to why I would have to map
> > the physical address to the virtual address when I know that the string is
> > permanently in the physical memory because its loaded into flash. Is there a way
> > to directly read from the physical memory location? Also, do the functions
> > ioremap() and readl(va) work when called from within a kernel module?
> >
>
> Of course, if you look at almost any of the memory mapped device
> drivers, you will find that ioremap/readl/writel is the backbone of
> your infrastructure.
>
>
> Manu
>