Cachable / Non-cachable memory

Hi,

how does Linux specify memory regions as cachable and non-
cachable? It is sometimes required to mark mapped memory
regions from devices as non-cachable by the MMU so the PowerPC
does not tune the write/read accesses.

Is there any function or sample driver code in the mpc8xx-linux
2.2.13 code ?

cu Raphael Bossek - http://www.solutions4linux.de/powerpc.html

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raphael.bossek@solutions4linux.de wrote:

how does Linux specify memory regions as cachable and non-
cachable?

Any memory mapping request outside of the range of real
memory is mapped uncached/guarded.  Look at drivers/char/mem.c

Driver requests to ioremap() are mapped uncached/guarded.


	-- Dan

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