From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] Fix IXP4xx coherent allocations
Date: Sat, 23 Mar 2013 19:57:40 -0400 (EDT)
Message-ID: <20130323.195740.2108147521543354261.davem@davemloft.net>
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=46rom: Krzysztof Halasa <khc@pm.waw.pl>
Date: Sat, 23 Mar 2013 20:35:46 +0100

> ARM core code currently requires coherent DMA mask to be set. Make su=
re
> we limit PCI devices to 64 MiB while allowing on-chip devices to acce=
ss
> the whole 4 GiB address space.
>=20
> This fixes a v3.7+ regression which broke IXP4xx built-in network dev=
ices.
>=20
> Signed-off-by: Krzysztof Ha=A9=A9asa <khc@pm.waw.pl>

This requirement is not reasonable.

The DMA API documentation clearly states what the default must be,
and what drivers are guarenteed will be the default.