lkml.org 
[lkml]   [2016]   [Oct]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Subject[net-next PATCH 22/27] arch/xtensa: Add option to skip DMA sync as a part of mapping
    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: Max Filippov <jcmvbkbc@gmail.com>
    Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
    ---
    arch/xtensa/kernel/pci-dma.c | 7 +++++--
    1 file changed, 5 insertions(+), 2 deletions(-)

    diff --git a/arch/xtensa/kernel/pci-dma.c b/arch/xtensa/kernel/pci-dma.c
    index 1e68806..6a16dec 100644
    --- a/arch/xtensa/kernel/pci-dma.c
    +++ b/arch/xtensa/kernel/pci-dma.c
    @@ -189,7 +189,9 @@ static dma_addr_t xtensa_map_page(struct device *dev, struct page *page,
    {
    dma_addr_t dma_handle = page_to_phys(page) + offset;

    - xtensa_sync_single_for_device(dev, dma_handle, size, dir);
    + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
    + xtensa_sync_single_for_device(dev, dma_handle, size, dir);
    +
    return dma_handle;
    }

    @@ -197,7 +199,8 @@ static void xtensa_unmap_page(struct device *dev, dma_addr_t dma_handle,
    size_t size, enum dma_data_direction dir,
    unsigned long attrs)
    {
    - xtensa_sync_single_for_cpu(dev, dma_handle, size, dir);
    + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
    + xtensa_sync_single_for_cpu(dev, dma_handle, size, dir);
    }

    static int xtensa_map_sg(struct device *dev, struct scatterlist *sg,
    \
     
     \ /
      Last update: 2016-10-25 23:41    [W:4.222 / U:0.200 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site