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    SubjectRe: [PATCH] fix misalignment in pxamci
    On Mon, Jul 28, 2008 at 6:23 PM, Uli Luckas <u.luckas@road.de> wrote:
    > On Saturday, 5. July 2008, pHilipp Zabel wrote:
    >> On Sat, Jul 5, 2008 at 2:19 AM, Marek Vasut <marek.vasut@gmail.com> wrote:
    >> > Hi,
    >> > Philipp Zabel finally made the pxamci issue clear. It turned out, that
    >> > pxamci needs the DMA destination address to be aligned to 8 bytes. In
    >> > some cases it happened, that the address was aligned to 4 bytes causing
    >> > controller to incorrectly transfer data (and resulting into error like
    >> > "mmc0: unrecognised SCR structure version 1"). The following patch allows
    >> > to debug this issue and moreover fixes it by moving one 4 byte entry of
    >> > mmc_card structure, aligning the DMA destination back to 8 bytes.
    >> >
    >> > Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
    >>
    >> We can enable byte aligned transfers on the DMA controller. This is
    >> what I came up with yesterday:
    >> (sorry for wrapped lines - the proper patch should probably be a
    >> combination of both
    >> warning/DALGN handling and and moving something in mmc_card around).
    >>
    > Hi Philipp,
    > this driver is not only for pxa27x but for pxa25x as well and pxa25x can't
    > handle unaligned DMA.
    > Shouldn't Marek Vasut's patch be included for the PXA25x case?

    Argh, DALGN shouldn't be defined in pxa-regs.h. We really need an
    aligned SCR target then. Pierre, is there any way we can have the MMC
    core align DMA targets for pxa25x?

    Just moving elements of the mmc_card structure around seems to be good
    enough, but I fear this will break again as soon as the next person
    forgets about pxamci's special needs on pxa25x.

    regards
    Philipp


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