Re: [PATCH 2/3] powerpc/esdhc: add property to disable the CMD23

On Sep 12, 2012, at 1:18 AM, Huang Changming-R66093 wrote:

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Best Regards
Jerry Huang
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-----Original Message-----
From: Chris Ball [mailto:cjb@laptop.org]
Sent: Wednesday, September 12, 2012 4:59 AM
To: Kumar Gala
Cc: Huang Changming-R66093; linuxppc-dev@lists.ozlabs.org list; =

linux-

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mmc@vger.kernel.org; Anton Vorontsov
Subject: Re: [PATCH 2/3] powerpc/esdhc: add property to disable the =

CMD23

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Hi,
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On Tue, Sep 11 2012, Kumar Gala wrote:

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thanks for the info.  Do you know what's required on controller side
to handle cards that support CMD23?
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I'm trying to figure out if older controller's on FSL SoCs are =

missing

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some feature to allow CMD23 to work (vs Auto-CMD23).

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It seems plausible that it's just not implemented on these =

controllers.

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It's a little strange, since the command's been specified for so long =

and

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we haven't seen any other controllers with problems.  The patch would =

be

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correct if this is true.
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I didn't find any description about it, but after testing on FSL =

silicones, I got this result:

Some silicones support this command, and some silicones don't support =

it, which will cause I/O error.

Can you list out which SoCs support it and which don't.  Having this =
list will be useful in understanding which controller versions supported =
it.

- k=