lkml.org 
[lkml]   [2016]   [Oct]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Subject[net-next PATCH RFC 12/26] arch/microblaze: Add option to skip DMA sync as a part of map and unmap
    From
    Date
    This change allows us to pass DMA_ATTR_SKIP_CPU_SYNC which allows us to
    avoid invoking cache line invalidation if the driver will just handle it
    via a sync_for_cpu or sync_for_device call.

    Cc: Michal Simek <monstr@monstr.eu>
    Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
    ---
    arch/microblaze/kernel/dma.c | 10 ++++++++--
    1 file changed, 8 insertions(+), 2 deletions(-)

    diff --git a/arch/microblaze/kernel/dma.c b/arch/microblaze/kernel/dma.c
    index ec04dc1..818daf2 100644
    --- a/arch/microblaze/kernel/dma.c
    +++ b/arch/microblaze/kernel/dma.c
    @@ -61,6 +61,10 @@ static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
    /* FIXME this part of code is untested */
    for_each_sg(sgl, sg, nents, i) {
    sg->dma_address = sg_phys(sg);
    +
    + if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
    + continue;
    +
    __dma_sync(page_to_phys(sg_page(sg)) + sg->offset,
    sg->length, direction);
    }
    @@ -80,7 +84,8 @@ static inline dma_addr_t dma_direct_map_page(struct device *dev,
    enum dma_data_direction direction,
    unsigned long attrs)
    {
    - __dma_sync(page_to_phys(page) + offset, size, direction);
    + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
    + __dma_sync(page_to_phys(page) + offset, size, direction);
    return page_to_phys(page) + offset;
    }

    @@ -95,7 +100,8 @@ static inline void dma_direct_unmap_page(struct device *dev,
    * phys_to_virt is here because in __dma_sync_page is __virt_to_phys and
    * dma_address is physical address
    */
    - __dma_sync(dma_address, size, direction);
    + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
    + __dma_sync(dma_address, size, direction);
    }

    static inline void
    \
     
     \ /
      Last update: 2016-10-24 20:12    [W:4.241 / U:0.156 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site