Re: [PATCH 3/3] MIPS: DMA: Add plat_extra_sync_for_cpu()

[David Daney]

On 09/08/2010 04:02 PM, Kevin Cernekee wrote:
> On noncoherent processors with a readahead cache, an extra platform-
> specific invalidation is required during the dma_sync_*_for_cpu()
> operations to keep drivers from seeing stale prefetched data.
>
> Signed-off-by: Kevin Cernekee<cernekee@xxxxxxxxx>
> ---
>   .../include/asm/mach-cavium-octeon/dma-coherence.h |   13 +++++++++++++
>   arch/mips/include/asm/mach-generic/dma-coherence.h |   13 +++++++++++++
>   arch/mips/include/asm/mach-ip27/dma-coherence.h    |   13 +++++++++++++
>   arch/mips/include/asm/mach-ip32/dma-coherence.h    |   13 +++++++++++++
>   arch/mips/include/asm/mach-jazz/dma-coherence.h    |   13 +++++++++++++
>   .../mips/include/asm/mach-loongson/dma-coherence.h |   13 +++++++++++++
>   arch/mips/include/asm/mach-powertv/dma-coherence.h |   13 +++++++++++++
>   arch/mips/mm/dma-default.c                         |    3 +++
>   8 files changed, 94 insertions(+), 0 deletions(-)
[...]

But as far as I can see, none of your plat_extra_sync_for_cpu() do anything.

Perhaps adding this hook should be deferred until there is actually a user.

David Daney
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