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    SubjectRE: dmaengine/Query: What about scatter/gather for mem to mem transfers.
    Date
    > 
    > Hello Vinod/Dan,
    >
    > Please write your opinion.
    I am on vacation, but will reply briefly here, more next week
    >
    > Regards
    > Pratyush
    >
    > On 12/14/2011 12:17 PM, Pratyush Anand wrote:
    > > Hello Vinod/Dan,
    > >
    > > In continuation to the scatter/gather requirement:
    > > We might need some generic transfer where source and destination
    > > address may be overlapped and also gap between two chunk of source and
    > > destination might not be same.
    > >
    > > For examaple,
    > > Transfer size is - -0x4000
    > > Our Src is something like this:
    > > 0x1000 -- 0x2000
    > > 0x3000 -- 0x5000
    > > 0x6000 -- 0x7000
    > >
    > > and dst is something like this:
    > > 0x6000 -- 0x8000
    > > 0x9000 -- 0xB000
    So why can't it be split like:
    0x1000--0x2000 => 0x6000 --0x7000
    0x3000 -- 0x4000 => 0x7000 - 0x8000
    0x4000 -- 0x5000 => 0x9000 - 0xA000
    0x6000 -- 0x7000 => 0xA000 - 0xB000

    That way existing mechanism would work well for you.
    You need to split the chunks properly, which is what dma would do anyway

    --
    ~Vinod
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