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    SubjectRe: [PATCH 0/8] sdhci: Move real work out of an atomic context
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    On Wed, 14 Jul 2010 17:07:28 +0400, Anton Vorontsov <avorontsov@mvista.com> wrote:
    > Hi all,
    >
    > Currently the sdhci driver does everything in the atomic context.
    > And what is worse, PIO transfers are made from the IRQ handler.
    >
    > This causes huge latencies (up to 120 ms). On some P2020 SOCs,
    > DMA and card detection is broken, which means that kernel polls
    > for the card via PIO transfers every second. Needless to say
    > that this is quite bad.
    >
    > So, this patch set reworks sdhci code to avoid atomic context,
    > almost completely. We only do two device memory operations
    > in the atomic context, and all the rest is threaded.
    >
    > I noticed no throughput drop neither with PIO transfers nor
    > with DMA (tested on MPC8569E CPU), while latencies should be
    > greatly improved.

    I haven't had time to read these patches in detail yet but they all seem
    to be sensible changes. A very nice series!


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