From: "Grant Likely" <grant.likely@secretlab.ca>
To: "Misbah khan" <misbah_khan@engineer.com>
Cc: linuxppc-embedded@ozlabs.org
Subject: Re: Ioremap related concern ...
Date: Wed, 17 Sep 2008 23:12:54 -0700 [thread overview]
Message-ID: <fa686aa40809172312r6f527e1ahbae83b17f8062c62@mail.gmail.com> (raw)
In-Reply-To: <19545826.post@talk.nabble.com>
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.
prev parent reply other threads:[~2008-09-18 6:12 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-09-18 4:43 Ioremap related concern Misbah khan
2008-09-18 6:12 ` Grant Likely [this message]
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