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Re: 1024bytes/sect microSD support



Hi! Paul,


From: KIYOHARA Takashi <kiyohara%kk.iij4u.or.jp@localhost>
Date: Fri, 27 Nov 2009 20:05:36 +0900 (JST)

> From: Paul Fleischer <paul%xpg.dk@localhost>
> Date: Fri, 27 Nov 2009 10:50:49 +0100
> 
> > As far as I can read from the SD Simplified Physical Layer
> > Specification[1] page 19, the 2Gb cards are bit of an exception as
> > their CSD announces a block size of 1024, but the actual block size to
> > use is 512kb.
> > 
> > I have patched dev/sdmmc/sdmmc_mem.c to follow this exception. I bet
> > the patch can be made more pretty, but it seems to work.
> 
> Your patch works to my microSD on GUMSTIX.
> A lot of people will think this patch to be necessary.

I was wrong report.  I apologize with the mail before.  I had forgotten
having changed pxamci for the test.  Your patch was 1961*1024 though my
microSD was 1985024 sectors.

  my microSD:
    ld0: 1938 MB, 984 cyl, 32 head, 63 sec, 1024 bytes/sect x 1985024 sectors

  your patch:
    if ( (1<<csd->read_bl_len)*csd->capacity >= 1961*1024*1024 ) {
       is_2gb_v1_card = 1;
    }

Thanks,
--
kiyohara


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