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Date: Sat, 25 Mar 2006 09:17:23 +1100
From: Paul Mackerras <paulus@samba.org>
To: Kallol Biswas <Kallol_Biswas@pmc-sierra.com>
Subject: RE: memory with __get_free_pages and disabling caching
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Kallol Biswas writes:

> We have a little endian device on a PPC 440GX based system.
> The descriptors need to be swapped. With E bit turned on we can save
> swapping time.

Writing the descriptors with stwbrx should be just as fast as using
stw, and eliminates the need for a special mapping.

If you need it to be cache-inhibited, you should be using
dma_alloc_coherent() or pci_alloc_consistent().

Paul.