[PATCH] mmc: core: Fix the incorrect calculation for erase unit size.

[PATCH] mmc: core: Fix the incorrect calculation for erase unit size.

[Seungwon Jeon]

Erase unit size of high capacity is multiple of 512KiB not 1024KiB.

Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
---
 drivers/mmc/core/mmc.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index b148bb1..7991ecf 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -332,7 +332,7 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd)
 		card->ext_csd.hc_erase_timeout = 300 *
 			ext_csd[EXT_CSD_ERASE_TIMEOUT_MULT];
 		card->ext_csd.hc_erase_size =
-			ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE] << 10;
+			ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE] << 9;

 		card->ext_csd.rel_sectors = ext_csd[EXT_CSD_REL_WR_SEC_C];

--
1.7.0.4

Re: [PATCH] mmc: core: Fix the incorrect calculation for erase unit size.

[Kyungmin Park]

Acked-by: Kyungmin Park <kyungmin.park@samsung.com>

On Thu, Sep 8, 2011 at 2:59 PM, Seungwon Jeon <tgih.jun@samsung.com> wrote:
> Erase unit size of high capacity is multiple of 512KiB not 1024KiB.
>
> Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
> ---
>  drivers/mmc/core/mmc.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
> index b148bb1..7991ecf 100644
> --- a/drivers/mmc/core/mmc.c
> +++ b/drivers/mmc/core/mmc.c
> @@ -332,7 +332,7 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd)
>                card->ext_csd.hc_erase_timeout = 300 *
>                        ext_csd[EXT_CSD_ERASE_TIMEOUT_MULT];
>                card->ext_csd.hc_erase_size =
> -                       ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE] << 10;
> +                       ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE] << 9;
>
>                card->ext_csd.rel_sectors = ext_csd[EXT_CSD_REL_WR_SEC_C];
>
> --
> 1.7.0.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
> the body of a message to majordomo@vger.kernel.org
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>

Re: [PATCH] mmc: core: Fix the incorrect calculation for erase unit size.

[Chris Ball]

Hi,

On Thu, Sep 08 2011, Seungwon Jeon wrote:
> Erase unit size of high capacity is multiple of 512KiB not 1024KiB.

Could we have some more info, please?  What are the visible symptoms
of the erase unit size being incorrect, how did you realize this was
a problem, should this patch be applied to stable@, etc.

Thanks,

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

Re: [PATCH] mmc: core: Fix the incorrect calculation for erase unit size.

[J Freyensee]

On 09/07/2011 10:59 PM, Seungwon Jeon wrote:
> Erase unit size of high capacity is multiple of 512KiB not 1024KiB.

I'm just wondering, what are these patches based off of?  I have not 
been able to connect to anything hosted by kernel.org since I came back 
from vacation due to the security breach on kernel.org.

>
> Signed-off-by: Seungwon Jeon<tgih.jun@samsung.com>
> ---
>   drivers/mmc/core/mmc.c |    2 +-
>   1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
> index b148bb1..7991ecf 100644
> --- a/drivers/mmc/core/mmc.c
> +++ b/drivers/mmc/core/mmc.c
> @@ -332,7 +332,7 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd)
>   		card->ext_csd.hc_erase_timeout = 300 *
>   			ext_csd[EXT_CSD_ERASE_TIMEOUT_MULT];
>   		card->ext_csd.hc_erase_size =
> -			ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE]<<  10;
> +			ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE]<<  9;
>
>   		card->ext_csd.rel_sectors = ext_csd[EXT_CSD_REL_WR_SEC_C];
>
> --
> 1.7.0.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html


-- 
J (James/Jay) Freyensee
Storage Technology Group
Intel Corporation

Re: [PATCH] mmc: core: Fix the incorrect calculation for erase unit size.

[ajh mls]

On 08/09/2011, Seungwon Jeon <tgih.jun@samsung.com> wrote:
> Erase unit size of high capacity is multiple of 512KiB not 1024KiB.

Isn't hc_erase_size in sectors so 512 x 1024 / 512 = 1024 and so the
code is correct.

>
> Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
> ---
>  drivers/mmc/core/mmc.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
> index b148bb1..7991ecf 100644
> --- a/drivers/mmc/core/mmc.c
> +++ b/drivers/mmc/core/mmc.c
> @@ -332,7 +332,7 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8
> *ext_csd)
>  		card->ext_csd.hc_erase_timeout = 300 *
>  			ext_csd[EXT_CSD_ERASE_TIMEOUT_MULT];
>  		card->ext_csd.hc_erase_size =
> -			ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE] << 10;
> +			ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE] << 9;
>
>  		card->ext_csd.rel_sectors = ext_csd[EXT_CSD_REL_WR_SEC_C];
>
> --
> 1.7.0.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>

RE: [PATCH] mmc: core: Fix the incorrect calculation for erase unit size.

[Seungwon Jeon]

Chris Ball wrote:
> 
> Hi,
> 
> On Thu, Sep 08 2011, Seungwon Jeon wrote:
> > Erase unit size of high capacity is multiple of 512KiB not 1024KiB.
> 
> Could we have some more info, please?  What are the visible symptoms
> of the erase unit size being incorrect, how did you realize this was
> a problem, should this patch be applied to stable@, etc.

It is mentioned from eMMC Spec.
Erase unit size is defined in 512Kbyte * HC_ERASE_GRP_SIZE(EXT_CSD[224]).

Thanks.

> 
> Thanks,
> 
> - Chris.
> --
> Chris Ball   <cjb@laptop.org>   <http://printf.net/>
> One Laptop Per Child

Re: [PATCH] mmc: core: Fix the incorrect calculation for erase unit size.

[Chris Ball]

Hi,

On Tue, Sep 13 2011, Seungwon Jeon wrote:
>> On Thu, Sep 08 2011, Seungwon Jeon wrote:
>> > Erase unit size of high capacity is multiple of 512KiB not 1024KiB.
>> 
>> Could we have some more info, please?  What are the visible symptoms
>> of the erase unit size being incorrect, how did you realize this was
>> a problem, should this patch be applied to stable@, etc.
>
> It is mentioned from eMMC Spec.
> Erase unit size is defined in 512Kbyte * HC_ERASE_GRP_SIZE(EXT_CSD[224]).

You haven't answered any of the other questions I asked, though.

Thanks,

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

RE: [PATCH] mmc: core: Fix the incorrect calculation for erase unit size.

[Seungwon Jeon]

Chris Ball wrote:
> 
> Hi,
> 
> On Tue, Sep 13 2011, Seungwon Jeon wrote:
> >> On Thu, Sep 08 2011, Seungwon Jeon wrote:
> >> > Erase unit size of high capacity is multiple of 512KiB not 1024KiB.
> >>
> >> Could we have some more info, please?  What are the visible symptoms
> >> of the erase unit size being incorrect, how did you realize this was
> >> a problem, should this patch be applied to stable@, etc.
> >
> > It is mentioned from eMMC Spec.
> > Erase unit size is defined in 512Kbyte * HC_ERASE_GRP_SIZE(EXT_CSD[224]).
> 
> You haven't answered any of the other questions I asked, though.

I didn't catch symptoms you expect. But it seems like plain.
I just noticed the difference with spec.

Best regards,
Seungwon Jeon.

> 
> Thanks,
> 
> - Chris.
> --
> Chris Ball   <cjb@laptop.org>   <http://printf.net/>
> One Laptop Per Child