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    SubjectRe: [PATCH 6/7] k3dma: Fix occasional DMA ERR issue by using proper dma api


    On 07/21/2016 11:53 AM, John Stultz wrote:
    > After lots of debugging on an occasional DMA ERR issue, I realized
    > that the desc structures which we point the dma hardware are being
    > allocated out of regular memory. This means when we fill the desc
    > structures, that data doesn't always get flushed out to memory by
    > the time we start the dma transfer, resulting in the dma engine getting
    > some null values, resulting in a DMA ERR on the first irq.

    How about using wmb() flush before start dma to sync desc?

    I remember I used dma_pool first, then do some optimization referring
    Russell's driver.

    Thanks

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