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Date: Wed, 17 Sep 2008 23:12:54 -0700
From: "Grant Likely" <grant.likely@secretlab.ca>
Sender: glikely@secretlab.ca
To: "Misbah khan" <misbah_khan@engineer.com>
Subject: Re: Ioremap related concern ...
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On Wed, Sep 17, 2008 at 9:43 PM, Misbah khan <misbah_khan@engineer.com> wrote:
>
> Hi all,
>
> i am facing a problem regarding the usage of ioremap function which is
> described as:-
>
> 1) I am remaping the SDRAM memory into three continews buffer as
>        ptr1 = (unsigned int *)ioremap(0x0001000,0x1000);
>        ptr2 = (unsigned int *)ioremap(0x0002000,0x1000);
>        ptr3 = (unsigned int *)ioremap(0x0003000,0x1000);

Ah, this doesn't work.  You can't just choose a region of ram and
ioremap it.  Besides, the base of RAM is already used by the interrupt
vectors.

If you need to allocate a region for DMA buffers, then take a look at
dma_alloc_coherent().  If you just need to allocate some buffers, then
just use kzalloc().

g.

-- 
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.