[U-Boot] [PATCH v3 4/4] mmc: sdhci: increase the timeout and udelay value

Jaehoon Chung jh80.chung at samsung.com
Mon Sep 3 04:44:11 CEST 2012


Hi Andy,

I understood your comment,
I will try to solve the problem.
(didn't change the udelay and loop count)
Then Could you merge the patch [1/4~3/4]?
I will debug more and resend the patch related with this problem.

If you can merge the patches[1/4~3/4], I think that other people can also debug this problem.
(if produce the problem.)

Best Regards,
Jaehoon Chung

On 09/01/2012 06:16 AM, Andy Fleming wrote:
> On Thu, Aug 30, 2012 at 7:24 PM, Jaehoon Chung <jh80.chung at samsung.com> wrote:
>> Samsung-SoC is taken the too late to changing the interrupt status register.
>> This patch is ensure to check the interrupt status register for Samsung-SoC.
>>
>> Signed-off-by: Jaehoon Chung <jh80.chung at samsung.com>
>> Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
>> ---
> 
> 
> You should write, here, what you changed in v3.
> 
> 
>>  drivers/mmc/sdhci.c |    4 ++--
>>  1 files changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
>> index ac39e48..d0b8d24 100644
>> --- a/drivers/mmc/sdhci.c
>> +++ b/drivers/mmc/sdhci.c
>> @@ -83,7 +83,7 @@ static int sdhci_transfer_data(struct sdhci_host *host, struct mmc_data *data,
>>  {
>>         unsigned int stat, rdy, mask, timeout, block = 0;
>>
>> -       timeout = 10000;
>> +       timeout = 100000;
>>         rdy = SDHCI_INT_SPACE_AVAIL | SDHCI_INT_DATA_AVAIL;
>>         mask = SDHCI_DATA_AVAILABLE | SDHCI_SPACE_AVAILABLE;
>>         do {
>> @@ -110,7 +110,7 @@ static int sdhci_transfer_data(struct sdhci_host *host, struct mmc_data *data,
>>                 }
>>  #endif
>>                 if (timeout-- > 0)
>> -                       udelay(10);
>> +                       udelay(20);
> 
> 
> ... This change makes no sense.
> 
> Actually, this whole *function* makes no sense. It seems to me that if
> you attempt to transfer more than 100000 blocks, it will fail. A
> timeout variable should only be used to control the number of
> iterations through a wait loop. This loop does more than wait, it also
> executes an ongoing, multiblock transfer.
> 
> I'm not exactly sure what issue this change is solving, but extending
> the delay, and increasing the number of iterations is *not* the
> solution. You're just hiding the problem.
> 
> You need to figure out why your transfer failed, and then modify the
> code to actually solve that problem. And I strongly think you need to
> refactor this transfer loop so that it properly transfers all desired
> blocks, and times out only when timeouts happen.
> 
> Andy
> 



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