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Subject: Re: [PATCH] powerpc: Fix swiotlb ops for ppc64
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From: Kumar Gala <galak@kernel.crashing.org>
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Date: Wed, 7 Dec 2011 23:46:54 -0600
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To: Becky Bruce <beckyb@kernel.crashing.org>
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On Dec 7, 2011, at 9:23 PM, Benjamin Herrenschmidt wrote:

> On Wed, 2011-12-07 at 11:19 -0600, Kumar Gala wrote:
>=20
>> struct dma_map_ops swiotlb_dma_ops =3D {
>> +#ifdef CONFIG_PPC64
>> +	.alloc_coherent =3D swiotlb_alloc_coherent,
>> +	.free_coherent =3D swiotlb_free_coherent,
>> +#else
>> 	.alloc_coherent =3D dma_direct_alloc_coherent,
>> 	.free_coherent =3D dma_direct_free_coherent,
>> +#endif
>> 	.map_sg =3D swiotlb_map_sg_attrs,
>> 	.unmap_sg =3D swiotlb_unmap_sg_attrs,
>> 	.dma_supported =3D swiotlb_dma_supported,
>=20
> Do we really need the ifdef ? What happens if we use
> swiotlb_alloc_coherent() on ppc32 ? Won't it allocate lowmem, realize
> that it doesn't need bouncing and be happy ?
>=20
> Cheers,
> Ben.

Becky any comment?

I know its been a while, but wondering if you had any reason to not do =
what Ben's suggesting ?

- k=