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Date: Wed, 4 Apr 2007 15:14:40 +1000
From: Paul Mackerras <paulus@samba.org>
To: Roland Dreier <rdreier@cisco.com>
Subject: Re: [PATCH] Allow drivers to map individual 4k pages to userspace
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Roland Dreier writes:

> If I'm going off on something irrelevant, just tell me.  But is there
> a chance that you would want to build a kernel that can boot on both a
> platform that has eHCA, and also on some other platform that cannot
> support remap_4k_pfn?

In a word, no. :)

Only 64-bit machines have eHCA.  A 64-bit powerpc kernel only supports
64-bit machines, and all 64-bit powerpc machines can support
remap_4k_pfn.  I don't see any difficulty arising with future 64-bit
embedded processors either.

Paul.