[RFC 0/2] fix dma_map_sg not to do barriers for each buffer

Randy Dunlap rdunlap at xenotime.net
Wed Feb 10 16:27:47 EST 2010


On 02/10/10 12:37, adharmap at codeaurora.org wrote:
> From: Abhijeet Dharmapurikar <adharmap at quicinc.com>
> 
> Please refer to the post here
> http://lkml.org/lkml/2010/1/4/347
> 
> These changes are to introduce barrierless dma_map_area and dma_unmap_area and
> use them to map the buffers in the scatterlist. For the last buffer, call
> the normal dma_map_area(aka with barriers) effectively executing the barrier
> at the end of the operation.
> 
> Note that the barrierless operations are implemented for few arm
> architectures only and I would implement for others once these are okayed by the
> community.

So when you add these interfaces for other architectures, you will also
update Documentation/DMA-API.txt,  right??


> Abhijeet Dharmapurikar (2):
>   dma: define barrierless versions of map and unmap area
>   dma: fix scatter-gather api to use barrierless map/unmap functions
> 
>  arch/arm/include/asm/cacheflush.h  |    9 +++
>  arch/arm/include/asm/dma-mapping.h |   82 +++++++++++++++++++++
>  arch/arm/mm/cache-v3.S             |    6 ++
>  arch/arm/mm/cache-v4.S             |    6 ++
>  arch/arm/mm/cache-v4wb.S           |   94 +++++++++++++++++-------
>  arch/arm/mm/cache-v4wt.S           |    6 ++
>  arch/arm/mm/cache-v6.S             |  139 +++++++++++++++++++++++++----------
>  arch/arm/mm/cache-v7.S             |  120 +++++++++++++++++++++++--------
>  arch/arm/mm/dma-mapping.c          |   55 +++++++++++++--
>  9 files changed, 414 insertions(+), 103 deletions(-)


-- 
~Randy



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