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Re: 1024bytes/sect microSD support



Hi,

> I has 2 problems with sdmmc and pxamci.
>
> I got a microSD.  My GUMSTIX reports this message with it.
>
>  ld0: 1938 MB, 984 cyl, 32 head, 63 sec, 1024 bytes/sect x 1985024 sectors
>
> It is 1024 bytes/sect card.  I can't mount, fdisk, and disklabel it.
> This reason is report 'read CRC error'(STAT_CRC_READ_ERROR and MMC_I_DAT_ERR)
> by pxamci.
> I try with following fix.  pxamci quit and work.  ;-)
>
> sys/arch/arm/xscale/pxa2x0_mci.c:pxamci_attach_sub() ---
>        /* Setup max block length */
>        if (CPU_IS_PXA270) {
> #if 0
>                sc->sc_maxblklen = 2048;
> #else
>                sc->sc_maxblklen = 512;
> #endif
>        } else {
>                sc->sc_maxblklen = 512;
>        }
> --- sys/arch/arm/xscale/pxa2x0_mci.c::pxamci_attach_sub()
>
>
> Also I know, Linux's drivers/mmc/card/block.c always set 512bytes.
>
>  mmc_blk_alloc()
>  {
>    :
>        /*
>         * Both SD and MMC specifications state (although a bit
>         * unclearly in the MMC case) that a block size of 512
>         * bytes must always be supported by the card.
>         */
>        md->block_bits = 9;
>    :
>  }
>
>
> I think that it is necessary to always adjust us to 512 bytes.  If this
> is not supported, we cannot have Linux and interchangeability.
> However, I do not know how to set more better it.  Does anyone have an
> idea?

How about attached patch?

Regards,
-- 
NONAKA Kimihiro

Attachment: sdmmc.diff
Description: Binary data



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