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    SubjectRe: [PATCH] Fix DMA on Dreamcast
    On 7/21/07, Adrian McMenamin <> wrote:
    > On 21/07/07, Peter Bortas <> wrote:
    > >
    > > Sidenote: Does Linux handle the Dreamcast DMA errata?
    > >
    > You need to explain what you mean (at least to me!).
    > If you mean will it degrade gracefully - not without this patch if set
    > to the (correct) defconfig. With iffy settings it will.

    If I remember correctly (and that's a big if since I last looked at it
    in 2001) some revisions of the Dreamcast hardware would sporadically
    lock up if you scheduled a new DMA request to quickly after a previous
    one, even if you checked the ready bit. It's worked around by a delay
    of X microseconds as recommended by Sega engineers. I don't remember
    the value of X, nor where exactly in the flow this workaround should
    be applied.

    Adding Marcus in case he has a better memory than me.

    Peter Bortas
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