[PATCH] mmc: dw_mmc-exynos: fixed wrong sample-clock selection

[PATCH] mmc: dw_mmc-exynos: fixed wrong sample-clock selection

[Jaehoon Chung]

Almost all case is selected to 0.
(It's not correct sample-clock value.)
Since it set to wrong value, HS200 mode don't work fine.
If we want to select the correct value, it has to check from 1 to 7.(skip 0)

Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
---
 drivers/mmc/host/dw_mmc-exynos.c |    9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
index 0fbc53a..5294035 100644
--- a/drivers/mmc/host/dw_mmc-exynos.c
+++ b/drivers/mmc/host/dw_mmc-exynos.c
@@ -25,6 +25,7 @@
 #define NUM_PINS(x)			(x + 2)
 
 #define SDMMC_CLKSEL			0x09C
+#define SDMMC_CLKSEL_CCLK_SAMPLE_MASK	0x7
 #define SDMMC_CLKSEL_CCLK_SAMPLE(x)	(((x) & 7) << 0)
 #define SDMMC_CLKSEL_CCLK_DRIVE(x)	(((x) & 7) << 16)
 #define SDMMC_CLKSEL_CCLK_DIVIDER(x)	(((x) & 7) << 24)
@@ -330,6 +331,12 @@ static int dw_mci_exynos_execute_tuning(struct dw_mci_slot *slot, u32 opcode,
 	if (!blk_test)
 		return -ENOMEM;
 
+	/*
+	 * In order to check all selclk_sample clock,
+	 * it needs to reset to 0.
+	 */
+	dw_mci_exynos_set_clksmpl(host, 0);
+
 	start_smpl = dw_mci_exynos_get_clksmpl(host);
 
 	do {
@@ -372,7 +379,7 @@ static int dw_mci_exynos_execute_tuning(struct dw_mci_slot *slot, u32 opcode,
 				"Tuning error: cmd.error:%d, data.error:%d\n",
 				cmd.error, data.error);
 		}
-	} while (start_smpl != smpl);
+	} while (start_smpl < SDMMC_CLKSEL_CCLK_SAMPLE_MASK);
 
 	found = dw_mci_exynos_get_best_clksmpl(candiates);
 	if (found >= 0)
-- 
1.7.9.5

Re: [PATCH] mmc: dw_mmc-exynos: fixed wrong sample-clock selection

[Alim Akhtar]

Hi Jaehoon,

On Mon, Sep 15, 2014 at 3:56 PM, Jaehoon Chung <jh80.chung@samsung.com> wrote:
> Almost all case is selected to 0.
> (It's not correct sample-clock value.)
> Since it set to wrong value, HS200 mode don't work fine.
Can you please explain what problem you are facing here?
It is not clear from your patch description.
> If we want to select the correct value, it has to check from 1 to 7.(skip 0)
>
> Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
> ---
>  drivers/mmc/host/dw_mmc-exynos.c |    9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
> index 0fbc53a..5294035 100644
> --- a/drivers/mmc/host/dw_mmc-exynos.c
> +++ b/drivers/mmc/host/dw_mmc-exynos.c
> @@ -25,6 +25,7 @@
>  #define NUM_PINS(x)                    (x + 2)
>
>  #define SDMMC_CLKSEL                   0x09C
> +#define SDMMC_CLKSEL_CCLK_SAMPLE_MASK  0x7
>  #define SDMMC_CLKSEL_CCLK_SAMPLE(x)    (((x) & 7) << 0)
>  #define SDMMC_CLKSEL_CCLK_DRIVE(x)     (((x) & 7) << 16)
>  #define SDMMC_CLKSEL_CCLK_DIVIDER(x)   (((x) & 7) << 24)
> @@ -330,6 +331,12 @@ static int dw_mci_exynos_execute_tuning(struct dw_mci_slot *slot, u32 opcode,
>         if (!blk_test)
>                 return -ENOMEM;
>
> +       /*
> +        * In order to check all selclk_sample clock,
> +        * it needs to reset to 0.
> +        */
> +       dw_mci_exynos_set_clksmpl(host, 0);
> +
>         start_smpl = dw_mci_exynos_get_clksmpl(host);
>
>         do {
> @@ -372,7 +379,7 @@ static int dw_mci_exynos_execute_tuning(struct dw_mci_slot *slot, u32 opcode,
>                                 "Tuning error: cmd.error:%d, data.error:%d\n",
>                                 cmd.error, data.error);
>                 }
> -       } while (start_smpl != smpl);
> +       } while (start_smpl < SDMMC_CLKSEL_CCLK_SAMPLE_MASK);
>
>         found = dw_mci_exynos_get_best_clksmpl(candiates);
>         if (found >= 0)
> --
> 1.7.9.5
>
> --
> 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



-- 
Regards,
Alim

Re: [PATCH] mmc: dw_mmc-exynos: fixed wrong sample-clock selection

[Jaehoon Chung]

Hi, Alim.

On 09/17/2014 07:27 AM, Alim Akhtar wrote:
> Hi Jaehoon,
> 
> On Mon, Sep 15, 2014 at 3:56 PM, Jaehoon Chung <jh80.chung@samsung.com> wrote:
>> Almost all case is selected to 0.
>> (It's not correct sample-clock value.)
>> Since it set to wrong value, HS200 mode don't work fine.
> Can you please explain what problem you are facing here?

When i try to use HS200 with some eMMC card, Some card is working fine and other isn't working fine.
(DWMMC is occured the DCRC error.)
DCRC error might be occurred when the wrong sample-clock is set.
So i tried to see what value is selected to sample-clock.
(Selected value - Working fine card : 0, Not working fine card : 0)

When i skip to 0, it's selected to other value for best sample-clock.
(Selected value - Working fine card : 4, Not working fine card : 6)

After working fine card is selected to 6, it's working fine.
I didn't know which value is set for other card. But in my case, best sample-clock is selected to 0.

I think it has the some problem for selecting the sample-clock.

Best Regards,
Jaehoon Chung

> It is not clear from your patch description.
>> If we want to select the correct value, it has to check from 1 to 7.(skip 0)
>>
>> Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
>> ---
>>  drivers/mmc/host/dw_mmc-exynos.c |    9 ++++++++-
>>  1 file changed, 8 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
>> index 0fbc53a..5294035 100644
>> --- a/drivers/mmc/host/dw_mmc-exynos.c
>> +++ b/drivers/mmc/host/dw_mmc-exynos.c
>> @@ -25,6 +25,7 @@
>>  #define NUM_PINS(x)                    (x + 2)
>>
>>  #define SDMMC_CLKSEL                   0x09C
>> +#define SDMMC_CLKSEL_CCLK_SAMPLE_MASK  0x7
>>  #define SDMMC_CLKSEL_CCLK_SAMPLE(x)    (((x) & 7) << 0)
>>  #define SDMMC_CLKSEL_CCLK_DRIVE(x)     (((x) & 7) << 16)
>>  #define SDMMC_CLKSEL_CCLK_DIVIDER(x)   (((x) & 7) << 24)
>> @@ -330,6 +331,12 @@ static int dw_mci_exynos_execute_tuning(struct dw_mci_slot *slot, u32 opcode,
>>         if (!blk_test)
>>                 return -ENOMEM;
>>
>> +       /*
>> +        * In order to check all selclk_sample clock,
>> +        * it needs to reset to 0.
>> +        */
>> +       dw_mci_exynos_set_clksmpl(host, 0);
>> +
>>         start_smpl = dw_mci_exynos_get_clksmpl(host);
>>
>>         do {
>> @@ -372,7 +379,7 @@ static int dw_mci_exynos_execute_tuning(struct dw_mci_slot *slot, u32 opcode,
>>                                 "Tuning error: cmd.error:%d, data.error:%d\n",
>>                                 cmd.error, data.error);
>>                 }
>> -       } while (start_smpl != smpl);
>> +       } while (start_smpl < SDMMC_CLKSEL_CCLK_SAMPLE_MASK);
>>
>>         found = dw_mci_exynos_get_best_clksmpl(candiates);
>>         if (found >= 0)
>> --
>> 1.7.9.5
>>
>> --
>> 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: dw_mmc-exynos: fixed wrong sample-clock selection

[Alim Akhtar]

Hi Jaehoon

On Wed, Sep 17, 2014 at 8:06 AM, Jaehoon Chung <jh80.chung@samsung.com> wrote:
> Hi, Alim.
>
> On 09/17/2014 07:27 AM, Alim Akhtar wrote:
>> Hi Jaehoon,
>>
>> On Mon, Sep 15, 2014 at 3:56 PM, Jaehoon Chung <jh80.chung@samsung.com> wrote:
>>> Almost all case is selected to 0.
>>> (It's not correct sample-clock value.)
>>> Since it set to wrong value, HS200 mode don't work fine.
>> Can you please explain what problem you are facing here?
>
> When i try to use HS200 with some eMMC card, Some card is working fine and other isn't working fine.
> (DWMMC is occured the DCRC error.)
> DCRC error might be occurred when the wrong sample-clock is set.
> So i tried to see what value is selected to sample-clock.
> (Selected value - Working fine card : 0, Not working fine card : 0)
>
> When i skip to 0, it's selected to other value for best sample-clock.
> (Selected value - Working fine card : 4, Not working fine card : 6)
>
> After working fine card is selected to 6, it's working fine.
> I didn't know which value is set for other card. But in my case, best sample-clock is selected to 0.
I am not if this is only reason for the failure on you board.
When I tested this patch on my exynos5800 based Pi board, HS200 does
not work at all. Even the eMMC card detection does not happening,
forget about getting a DCRC error.
Can you confirm what base kernel you are testing on? FYI, I am testing
on Ulf's -next branch, which has two recently merged patches specially
for HS200 on dw_mmc controller.
In case you are using the same branch as mine, then some more debug
log will be good for more analysis of the problem.
>
> I think it has the some problem for selecting the sample-clock.
>
> Best Regards,
> Jaehoon Chung
>
>> It is not clear from your patch description.
>>> If we want to select the correct value, it has to check from 1 to 7.(skip 0)
>>>
>>> Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
>>> ---
>>>  drivers/mmc/host/dw_mmc-exynos.c |    9 ++++++++-
>>>  1 file changed, 8 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
>>> index 0fbc53a..5294035 100644
>>> --- a/drivers/mmc/host/dw_mmc-exynos.c
>>> +++ b/drivers/mmc/host/dw_mmc-exynos.c
>>> @@ -25,6 +25,7 @@
>>>  #define NUM_PINS(x)                    (x + 2)
>>>
>>>  #define SDMMC_CLKSEL                   0x09C
>>> +#define SDMMC_CLKSEL_CCLK_SAMPLE_MASK  0x7
>>>  #define SDMMC_CLKSEL_CCLK_SAMPLE(x)    (((x) & 7) << 0)
>>>  #define SDMMC_CLKSEL_CCLK_DRIVE(x)     (((x) & 7) << 16)
>>>  #define SDMMC_CLKSEL_CCLK_DIVIDER(x)   (((x) & 7) << 24)
>>> @@ -330,6 +331,12 @@ static int dw_mci_exynos_execute_tuning(struct dw_mci_slot *slot, u32 opcode,
>>>         if (!blk_test)
>>>                 return -ENOMEM;
>>>
>>> +       /*
>>> +        * In order to check all selclk_sample clock,
>>> +        * it needs to reset to 0.
>>> +        */
>>> +       dw_mci_exynos_set_clksmpl(host, 0);
>>> +
>>>         start_smpl = dw_mci_exynos_get_clksmpl(host);
>>>
>>>         do {
>>> @@ -372,7 +379,7 @@ static int dw_mci_exynos_execute_tuning(struct dw_mci_slot *slot, u32 opcode,
>>>                                 "Tuning error: cmd.error:%d, data.error:%d\n",
>>>                                 cmd.error, data.error);
>>>                 }
>>> -       } while (start_smpl != smpl);
>>> +       } while (start_smpl < SDMMC_CLKSEL_CCLK_SAMPLE_MASK);
>>>
>>>         found = dw_mci_exynos_get_best_clksmpl(candiates);
>>>         if (found >= 0)
>>> --
>>> 1.7.9.5
>>>
>>> --
>>> 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
>>
>>
>>
>



-- 
Regards,
Alim

Re: [PATCH] mmc: dw_mmc-exynos: fixed wrong sample-clock selection

[Jaehoon Chung]

Hi, Alim.

On 09/17/2014 09:49 PM, Alim Akhtar wrote:
> Hi Jaehoon
> 
> On Wed, Sep 17, 2014 at 8:06 AM, Jaehoon Chung <jh80.chung@samsung.com> wrote:
>> Hi, Alim.
>>
>> On 09/17/2014 07:27 AM, Alim Akhtar wrote:
>>> Hi Jaehoon,
>>>
>>> On Mon, Sep 15, 2014 at 3:56 PM, Jaehoon Chung <jh80.chung@samsung.com> wrote:
>>>> Almost all case is selected to 0.
>>>> (It's not correct sample-clock value.)
>>>> Since it set to wrong value, HS200 mode don't work fine.
>>> Can you please explain what problem you are facing here?
>>
>> When i try to use HS200 with some eMMC card, Some card is working fine and other isn't working fine.
>> (DWMMC is occured the DCRC error.)
>> DCRC error might be occurred when the wrong sample-clock is set.
>> So i tried to see what value is selected to sample-clock.
>> (Selected value - Working fine card : 0, Not working fine card : 0)
>>
>> When i skip to 0, it's selected to other value for best sample-clock.
>> (Selected value - Working fine card : 4, Not working fine card : 6)
>>
>> After working fine card is selected to 6, it's working fine.
>> I didn't know which value is set for other card. But in my case, best sample-clock is selected to 0.
> I am not if this is only reason for the failure on you board.
> When I tested this patch on my exynos5800 based Pi board, HS200 does
> not work at all. Even the eMMC card detection does not happening,
> forget about getting a DCRC error.
> Can you confirm what base kernel you are testing on? FYI, I am testing
> on Ulf's -next branch, which has two recently merged patches specially
> for HS200 on dw_mmc controller.
> In case you are using the same branch as mine, then some more debug
> log will be good for more analysis of the problem.

Thanks for pointing out. Well, i didn't test with other boards.
So your testing is helpful to me. I think it's not my board's problem.
Do you ensure that sample-clock is correct value?

I tested with 3.16-kerenl. Which value is selected at exynos5800 board?
I will test with kernel on Ulf's repository.

Best Regards,
Jaehoon Chung

>>
>> I think it has the some problem for selecting the sample-clock.
>>
>> Best Regards,
>> Jaehoon Chung
>>
>>> It is not clear from your patch description.
>>>> If we want to select the correct value, it has to check from 1 to 7.(skip 0)
>>>>
>>>> Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
>>>> ---
>>>>  drivers/mmc/host/dw_mmc-exynos.c |    9 ++++++++-
>>>>  1 file changed, 8 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
>>>> index 0fbc53a..5294035 100644
>>>> --- a/drivers/mmc/host/dw_mmc-exynos.c
>>>> +++ b/drivers/mmc/host/dw_mmc-exynos.c
>>>> @@ -25,6 +25,7 @@
>>>>  #define NUM_PINS(x)                    (x + 2)
>>>>
>>>>  #define SDMMC_CLKSEL                   0x09C
>>>> +#define SDMMC_CLKSEL_CCLK_SAMPLE_MASK  0x7
>>>>  #define SDMMC_CLKSEL_CCLK_SAMPLE(x)    (((x) & 7) << 0)
>>>>  #define SDMMC_CLKSEL_CCLK_DRIVE(x)     (((x) & 7) << 16)
>>>>  #define SDMMC_CLKSEL_CCLK_DIVIDER(x)   (((x) & 7) << 24)
>>>> @@ -330,6 +331,12 @@ static int dw_mci_exynos_execute_tuning(struct dw_mci_slot *slot, u32 opcode,
>>>>         if (!blk_test)
>>>>                 return -ENOMEM;
>>>>
>>>> +       /*
>>>> +        * In order to check all selclk_sample clock,
>>>> +        * it needs to reset to 0.
>>>> +        */
>>>> +       dw_mci_exynos_set_clksmpl(host, 0);
>>>> +
>>>>         start_smpl = dw_mci_exynos_get_clksmpl(host);
>>>>
>>>>         do {
>>>> @@ -372,7 +379,7 @@ static int dw_mci_exynos_execute_tuning(struct dw_mci_slot *slot, u32 opcode,
>>>>                                 "Tuning error: cmd.error:%d, data.error:%d\n",
>>>>                                 cmd.error, data.error);
>>>>                 }
>>>> -       } while (start_smpl != smpl);
>>>> +       } while (start_smpl < SDMMC_CLKSEL_CCLK_SAMPLE_MASK);
>>>>
>>>>         found = dw_mci_exynos_get_best_clksmpl(candiates);
>>>>         if (found >= 0)
>>>> --
>>>> 1.7.9.5
>>>>
>>>> --
>>>> 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
>>>
>>>
>>>
>>
> 
> 
>