RE: [PATCH] SD/MMC: fix the issue of SDHC performance regression

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-----Original Message-----
From: linux-mmc-owner@xxxxxxxxxxxxxxx [mailto:linux-mmc-owner@xxxxxxxxxxxxxxx] On Behalf Of Chris Ball
Sent: Monday, November 07, 2011 9:20 PM
To: Liu Qiang-B32616
Cc: linux-mmc@xxxxxxxxxxxxxxx; Li Yang-R58472; Gala Kumar-B11780
Subject: Re: [PATCH] SD/MMC: fix the issue of SDHC performance regression

Hi,

On Mon, Nov 07 2011, Qiang Liu wrote:
> Low performance of SDHC (half of before) due to its frequency was set 
> to 25MHz, but not 50MHz (involved by commit id 
> 013909c4ffd16ded4895528b856fd8782df04dc6,
> add support for query function modes for uhs cards according to 
> Physical Layer SPEC V3.01).
>
> Set high speed max frequency according to response status of CMD6, but 
> not for SPEC Version. Response of switch command is first 
> consideration factor when set SDHC max working frequency. TRAN_SPEED 
> in CSD register will be seemed as the second factor.
>
> Signed-off-by: Qiang Liu <qiang.liu@xxxxxxxxxxxxx>

Have you seen:

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=f2815f68dabbb373fd1c9f0fd4a609d486697c2b
("mmc: sd: Handle SD3.0 cards not supporting UHS-I bus speed mode")

which is already in mainline?  I think your patch is identical.
[Liu Qiang] Yes, they are identical. Thanks a lot.

Thanks,

- Chris.
-- 
Chris Ball   <cjb@xxxxxxxxxx>   <http://printf.net/>
One Laptop Per Child
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