[Cbe-oss-dev] [patch 03/16] powerpc and x86_64: Initial port of PCIe endpoint device driver for Axon

[Christoph Hellwig]

On Tue, Mar 11, 2008 at 05:25:45AM +0100, Arnd Bergmann wrote:
> On Saturday 08 March 2008, Murali Iyer wrote:
> > +
> > +#ifdef    CONFIG_TB_AXON_MTRR_SMA
> > +#include <asm/mtrr.h>
> > +#endif
> 
> You just discovered a bad interface provided by the kernel.
> Instead of using that like the last few people did, you can
> help everyone by fixing this. The correct solution is to
> have an include/linux/mtrr.h file that you can include
> in your driver and that either includes asm/mtrr.h or
> provides no-op functions with the same names.

I don't think so.  Mtrr is a really nasty x86-specific low-level
interface.  There's not much point to generalize it.  The new change
page attribute interface in 2.6.25 is a better highlevel interface
but I'm not sure how suitable it is for axon.