Re: ioremap_nocache problem?

[Stephen C. Tweedie]

Hi,

On Thu, Jan 25, 2001 at 11:53:01AM -0600, Timur Tabi wrote:
> 
> > As in an MMIO aperture?  If its MMIO on the bus you should be able to 
> > just call ioremap with the bus address.  By nature of it being outside 
> > of real ram, it should automatically be uncached (unless you've set an 
> > MTRR over that region saying otherwise).
> 
> It's not outside of real RAM.  The device is inside real RAM (it sits on the
> DIMM itself), but I need to poke through the entire 4GB range to see how it
> responds.

kmap() is designed for that, not ioremap().  Is it absolutely
essential that your mapping is uncached?  If so, extending kmap() to
support kmap_nocache() would seem to make a lot more sense than using
ioremap(): kmap is there for temporarily poking around in high memory,
whereas ioremap is really intended to be used for persistent maps.

--Stephen