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    SubjectRe: sdio: set the functions' block size
    Pierre Ossman wrote:
    > On Tue, 31 Jul 2007 16:36:32 +0100
    > David Vrabel <david.vrabel@csr.com> wrote:
    >
    >> Prior to calling the driver's probe(), set the functions' block size
    >> to the largest that's supported by both the card and the driver.
    >>
    >> Signed-off-by: David Vrabel <david.vrabel@csr.com>
    >>
    >
    > Why a maximum size for the driver?

    For efficient use of the bus it is useful to pad transfers to a multiple
    of the block size. I reckoned it was potentially beneficial for drivers
    to use smaller blocks so less padding was required. However, after
    looking at some figures the per block overhead (28 clocks for a write)
    really does limit the transfer sizes where small block sizes is beneficial.

    I'll remove this. Drivers can still override the block size by calling
    sdio_set_block_size() directly.

    David
    --
    David Vrabel, Software Engineer, Drivers group Tel: +44 (0)1223 692562
    CSR plc, Churchill House, Cambridge Business Park, Cowley Road, CB4 0WZ


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