Re: [PATCH 00/03][RFC] Reusable UIO Platform Driver

From: Uwe Kleine-König
Date: Wed May 21 2008 - 05:01:09 EST


Magnus Damm wrote:
> On Wed, May 21, 2008 at 5:05 PM, Uwe Kleine-König
> <Uwe.Kleine-Koenig@xxxxxxxx> wrote:
> > @Magnus: Maybe you can provide the userspace part of the driver?
> > How is that mapping used there?
> [Added Matsubara-san as CC]
> Sure, here is a little test program. Have a look at "uio_mem". The
> "address" member contains the physical address that can be used for
> bus mastering DMA. Compare that to "iomem" which is the pointer to the
> virtual memory area in user space.
> Hope this helps!
Yes it does. I thought the physical address is stored in internal_addr
and the virtual in addr, but it's the other way round. Thanks.

Best regards

Uwe Kleine-König, Software Engineer
Digi International GmbH Branch Breisach, Küferstrasse 8, 79206 Breisach, Germany
Tax: 315/5781/0242 / VAT: DE153662976 / Reg. Amtsgericht Dortmund HRB 13962
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