allocating uncachable memory

[Ronald Wahl]

On Fri, 25 Aug 2000, Dan Malek wrote:

> > question again: How can I get an alias mapping (with _PAGE_NO_CACHE |
> > _PAGE_GUARDED) of some already mapped pages.
>
> There isn't anything generic right now.  A few of us are working on
> a solution, as there are other processors affected (IBM 4xx) as well.
> If you look at the uart or Ethernet drivers, you will notice they
> allocate pages of memory, track down the PTEs and set the attributes
> directly.  You can use that as an example.
>
> Don't forget that managing the caches in software (via flushes and
> invalidates) could actually provide better performance for data
> transfers due to the cache bursting available when caches are enabled.

Yeah, that's what i do currently. But I had to write an
invalidate_dcache_range() first. I used the code of
flush_dcache_range() and replaced dcbst by dcbi. Now it
seems to work. Thanks for this hint, Dan.

ron


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