2024-01-31 21:53:28

by Judith Mendez

[permalink] [raw]
Subject: [PATCH v1 2/5] mmc: sdhci_am654: Write ITAPDLY for DDR52 timing

For DDR52 timing, DLL is enabled but tuning is not carried
out, therefore the ITAPDLY value in PHY CTRL 4 register is
not correct. Fix this by writing ITAPDLY after enabling DLL.

Fixes: a161c45f2979 ("mmc: sdhci_am654: Enable DLL only for some speed modes")
Signed-off-by: Judith Mendez <[email protected]>
---
drivers/mmc/host/sdhci_am654.c | 27 +++++++++++++++------------
1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/drivers/mmc/host/sdhci_am654.c b/drivers/mmc/host/sdhci_am654.c
index a3798c9912f6..ff18a274b6f2 100644
--- a/drivers/mmc/host/sdhci_am654.c
+++ b/drivers/mmc/host/sdhci_am654.c
@@ -170,7 +170,19 @@ struct sdhci_am654_driver_data {
#define DLL_CALIB (1 << 4)
};

-static void sdhci_am654_setup_dll(struct sdhci_host *host, unsigned int clock)
+static void sdhci_am654_write_itapdly(struct sdhci_am654_data *sdhci_am654,
+ u32 itapdly)
+{
+ /* Set ITAPCHGWIN before writing to ITAPDLY */
+ regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPCHGWIN_MASK,
+ 0x1 << ITAPCHGWIN_SHIFT);
+ regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPDLYSEL_MASK,
+ itapdly << ITAPDLYSEL_SHIFT);
+ regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPCHGWIN_MASK, 0);
+}
+
+static void sdhci_am654_setup_dll(struct sdhci_host *host, unsigned int clock,
+ unsigned char timing)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_am654_data *sdhci_am654 = sdhci_pltfm_priv(pltfm_host);
@@ -236,17 +248,8 @@ static void sdhci_am654_setup_dll(struct sdhci_host *host, unsigned int clock)
dev_err(mmc_dev(host->mmc), "DLL failed to relock\n");
return;
}
-}

-static void sdhci_am654_write_itapdly(struct sdhci_am654_data *sdhci_am654,
- u32 itapdly)
-{
- /* Set ITAPCHGWIN before writing to ITAPDLY */
- regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPCHGWIN_MASK,
- 1 << ITAPCHGWIN_SHIFT);
- regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPDLYSEL_MASK,
- itapdly << ITAPDLYSEL_SHIFT);
- regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPCHGWIN_MASK, 0);
+ sdhci_am654_write_itapdly(sdhci_am654, sdhci_am654->itap_del_sel[timing]);
}

static void sdhci_am654_setup_delay_chain(struct sdhci_am654_data *sdhci_am654,
@@ -298,7 +301,7 @@ static void sdhci_am654_set_clock(struct sdhci_host *host, unsigned int clock)
regmap_update_bits(sdhci_am654->base, PHY_CTRL4, mask, val);

if (timing > MMC_TIMING_UHS_SDR25 && clock >= CLOCK_TOO_SLOW_HZ) {
- sdhci_am654_setup_dll(host, clock);
+ sdhci_am654_setup_dll(host, clock, timing);
sdhci_am654->dll_enable = true;
} else {
sdhci_am654_setup_delay_chain(sdhci_am654, timing);
--
2.34.1



2024-02-01 19:36:54

by Andrew Davis

[permalink] [raw]
Subject: Re: [PATCH v1 2/5] mmc: sdhci_am654: Write ITAPDLY for DDR52 timing

On 1/31/24 3:50 PM, Judith Mendez wrote:
> For DDR52 timing, DLL is enabled but tuning is not carried
> out, therefore the ITAPDLY value in PHY CTRL 4 register is
> not correct. Fix this by writing ITAPDLY after enabling DLL.
>
> Fixes: a161c45f2979 ("mmc: sdhci_am654: Enable DLL only for some speed modes")
> Signed-off-by: Judith Mendez <[email protected]>
> ---
> drivers/mmc/host/sdhci_am654.c | 27 +++++++++++++++------------
> 1 file changed, 15 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci_am654.c b/drivers/mmc/host/sdhci_am654.c
> index a3798c9912f6..ff18a274b6f2 100644
> --- a/drivers/mmc/host/sdhci_am654.c
> +++ b/drivers/mmc/host/sdhci_am654.c
> @@ -170,7 +170,19 @@ struct sdhci_am654_driver_data {
> #define DLL_CALIB (1 << 4)
> };
>
> -static void sdhci_am654_setup_dll(struct sdhci_host *host, unsigned int clock)
> +static void sdhci_am654_write_itapdly(struct sdhci_am654_data *sdhci_am654,
> + u32 itapdly)

This patch is confusing, looks like you switched the place of these two
functions, but diff is not really liking that. You can mess with
--diff-algorithm and the like to get a more readable patch. But in
this case why switch their spots at all?

Seems to be so you can call sdhci_am654_write_itapdly() from
sdhci_am654_setup_dll() without a forward declaration, instead
why not just call sdhci_am654_write_itapdly() after calling
sdhci_am654_setup_dll() below. That also saves to from having
to pass in `timing` to sdhci_am654_write_itapdly() just to
have it pass it right through to sdhci_am654_setup_dll().

Andrew

> +{
> + /* Set ITAPCHGWIN before writing to ITAPDLY */
> + regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPCHGWIN_MASK,
> + 0x1 << ITAPCHGWIN_SHIFT);
> + regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPDLYSEL_MASK,
> + itapdly << ITAPDLYSEL_SHIFT);
> + regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPCHGWIN_MASK, 0);
> +}
> +
> +static void sdhci_am654_setup_dll(struct sdhci_host *host, unsigned int clock,
> + unsigned char timing)
> {
> struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> struct sdhci_am654_data *sdhci_am654 = sdhci_pltfm_priv(pltfm_host);
> @@ -236,17 +248,8 @@ static void sdhci_am654_setup_dll(struct sdhci_host *host, unsigned int clock)
> dev_err(mmc_dev(host->mmc), "DLL failed to relock\n");
> return;
> }
> -}
>
> -static void sdhci_am654_write_itapdly(struct sdhci_am654_data *sdhci_am654,
> - u32 itapdly)
> -{
> - /* Set ITAPCHGWIN before writing to ITAPDLY */
> - regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPCHGWIN_MASK,
> - 1 << ITAPCHGWIN_SHIFT);
> - regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPDLYSEL_MASK,
> - itapdly << ITAPDLYSEL_SHIFT);
> - regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPCHGWIN_MASK, 0);
> + sdhci_am654_write_itapdly(sdhci_am654, sdhci_am654->itap_del_sel[timing]);
> }
>
> static void sdhci_am654_setup_delay_chain(struct sdhci_am654_data *sdhci_am654,
> @@ -298,7 +301,7 @@ static void sdhci_am654_set_clock(struct sdhci_host *host, unsigned int clock)
> regmap_update_bits(sdhci_am654->base, PHY_CTRL4, mask, val);
>
> if (timing > MMC_TIMING_UHS_SDR25 && clock >= CLOCK_TOO_SLOW_HZ) {
> - sdhci_am654_setup_dll(host, clock);
> + sdhci_am654_setup_dll(host, clock, timing);
> sdhci_am654->dll_enable = true;
> } else {
> sdhci_am654_setup_delay_chain(sdhci_am654, timing);

2024-02-06 21:58:29

by Judith Mendez

[permalink] [raw]
Subject: Re: [PATCH v1 2/5] mmc: sdhci_am654: Write ITAPDLY for DDR52 timing

Hi Andrew,

On 2/1/24 1:36 PM, Andrew Davis wrote:
> On 1/31/24 3:50 PM, Judith Mendez wrote:
>> For DDR52 timing, DLL is enabled but tuning is not carried
>> out, therefore the ITAPDLY value in PHY CTRL 4 register is
>> not correct. Fix this by writing ITAPDLY after enabling DLL.
>>
>> Fixes: a161c45f2979 ("mmc: sdhci_am654: Enable DLL only for some speed
>> modes")
>> Signed-off-by: Judith Mendez <[email protected]>
>> ---
>>   drivers/mmc/host/sdhci_am654.c | 27 +++++++++++++++------------
>>   1 file changed, 15 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/mmc/host/sdhci_am654.c
>> b/drivers/mmc/host/sdhci_am654.c
>> index a3798c9912f6..ff18a274b6f2 100644
>> --- a/drivers/mmc/host/sdhci_am654.c
>> +++ b/drivers/mmc/host/sdhci_am654.c
>> @@ -170,7 +170,19 @@ struct sdhci_am654_driver_data {
>>   #define DLL_CALIB    (1 << 4)
>>   };
>> -static void sdhci_am654_setup_dll(struct sdhci_host *host, unsigned
>> int clock)
>> +static void sdhci_am654_write_itapdly(struct sdhci_am654_data
>> *sdhci_am654,
>> +                      u32 itapdly)
>
> This patch is confusing, looks like you switched the place of these two
> functions, but diff is not really liking that. You can mess with
> --diff-algorithm and the like to get a more readable patch. But in
> this case why switch their spots at all?
>
> Seems to be so you can call sdhci_am654_write_itapdly() from
> sdhci_am654_setup_dll() without a forward declaration, instead
> why not just call sdhci_am654_write_itapdly() after calling
> sdhci_am654_setup_dll() below. That also saves to from having
> to pass in `timing` to sdhci_am654_write_itapdly() just to
> have it pass it right through to sdhci_am654_setup_dll().

Really the only reason I did this is because we call
sdhci_am654_write_itapdly() in sdhci_am654_setup_delay_chain and
I wanted to keep the flow for setting up DLL the same.
I agree the patch looks confusing, so I will fix this for v2.

~ Judith

> Andrew
>
>> +{
>> +    /* Set ITAPCHGWIN before writing to ITAPDLY */
>> +    regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPCHGWIN_MASK,
>> +               0x1 << ITAPCHGWIN_SHIFT);
>> +    regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPDLYSEL_MASK,
>> +               itapdly << ITAPDLYSEL_SHIFT);
>> +    regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPCHGWIN_MASK,
>> 0);
>> +}
>> +
>> +static void sdhci_am654_setup_dll(struct sdhci_host *host, unsigned
>> int clock,
>> +                  unsigned char timing)
>>   {
>>       struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>       struct sdhci_am654_data *sdhci_am654 =
>> sdhci_pltfm_priv(pltfm_host);
>> @@ -236,17 +248,8 @@ static void sdhci_am654_setup_dll(struct
>> sdhci_host *host, unsigned int clock)
>>           dev_err(mmc_dev(host->mmc), "DLL failed to relock\n");
>>           return;
>>       }
>> -}
>> -static void sdhci_am654_write_itapdly(struct sdhci_am654_data
>> *sdhci_am654,
>> -                      u32 itapdly)
>> -{
>> -    /* Set ITAPCHGWIN before writing to ITAPDLY */
>> -    regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPCHGWIN_MASK,
>> -               1 << ITAPCHGWIN_SHIFT);
>> -    regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPDLYSEL_MASK,
>> -               itapdly << ITAPDLYSEL_SHIFT);
>> -    regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPCHGWIN_MASK,
>> 0);
>> +    sdhci_am654_write_itapdly(sdhci_am654,
>> sdhci_am654->itap_del_sel[timing]);
>>   }
>>   static void sdhci_am654_setup_delay_chain(struct sdhci_am654_data
>> *sdhci_am654,
>> @@ -298,7 +301,7 @@ static void sdhci_am654_set_clock(struct
>> sdhci_host *host, unsigned int clock)
>>       regmap_update_bits(sdhci_am654->base, PHY_CTRL4, mask, val);
>>       if (timing > MMC_TIMING_UHS_SDR25 && clock >= CLOCK_TOO_SLOW_HZ) {
>> -        sdhci_am654_setup_dll(host, clock);
>> +        sdhci_am654_setup_dll(host, clock, timing);
>>           sdhci_am654->dll_enable = true;
>>       } else {
>>           sdhci_am654_setup_delay_chain(sdhci_am654, timing);


2024-02-06 22:10:52

by Judith Mendez

[permalink] [raw]
Subject: Re: [PATCH v1 2/5] mmc: sdhci_am654: Write ITAPDLY for DDR52 timing

On 2/6/24 3:58 PM, Judith Mendez wrote:
> Hi Andrew,
>
> On 2/1/24 1:36 PM, Andrew Davis wrote:
>> On 1/31/24 3:50 PM, Judith Mendez wrote:
>>> For DDR52 timing, DLL is enabled but tuning is not carried
>>> out, therefore the ITAPDLY value in PHY CTRL 4 register is
>>> not correct. Fix this by writing ITAPDLY after enabling DLL.
>>>
>>> Fixes: a161c45f2979 ("mmc: sdhci_am654: Enable DLL only for some
>>> speed modes")
>>> Signed-off-by: Judith Mendez <[email protected]>
>>> ---
>>>   drivers/mmc/host/sdhci_am654.c | 27 +++++++++++++++------------
>>>   1 file changed, 15 insertions(+), 12 deletions(-)
>>>
>>> diff --git a/drivers/mmc/host/sdhci_am654.c
>>> b/drivers/mmc/host/sdhci_am654.c
>>> index a3798c9912f6..ff18a274b6f2 100644
>>> --- a/drivers/mmc/host/sdhci_am654.c
>>> +++ b/drivers/mmc/host/sdhci_am654.c
>>> @@ -170,7 +170,19 @@ struct sdhci_am654_driver_data {
>>>   #define DLL_CALIB    (1 << 4)
>>>   };
>>> -static void sdhci_am654_setup_dll(struct sdhci_host *host, unsigned
>>> int clock)
>>> +static void sdhci_am654_write_itapdly(struct sdhci_am654_data
>>> *sdhci_am654,
>>> +                      u32 itapdly)
>>
>> This patch is confusing, looks like you switched the place of these two
>> functions, but diff is not really liking that. You can mess with
>> --diff-algorithm and the like to get a more readable patch. But in
>> this case why switch their spots at all?
>>
>> Seems to be so you can call sdhci_am654_write_itapdly() from
>> sdhci_am654_setup_dll() without a forward declaration, instead
>> why not just call sdhci_am654_write_itapdly() after calling
>> sdhci_am654_setup_dll() below. That also saves to from having
>> to pass in `timing` to sdhci_am654_write_itapdly() just to
>> have it pass it right through to sdhci_am654_setup_dll().
>
> Really the only reason I did this is because we call
> sdhci_am654_write_itapdly() in sdhci_am654_setup_delay_chain and
> I wanted to keep the flow for setting up DLL the same.
> I agree the patch looks confusing, so I will fix this for v2.

TBH I think it is a good idea to keep the flow the same as it
is for sdhci_am654_setup_delay_chain(). Unless you know of a
strong enough reason to change, I am leaning towards leaving the
patch as is.

>
> ~ Judith
>
>> Andrew
>>
>>> +{
>>> +    /* Set ITAPCHGWIN before writing to ITAPDLY */
>>> +    regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPCHGWIN_MASK,
>>> +               0x1 << ITAPCHGWIN_SHIFT);
>>> +    regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPDLYSEL_MASK,
>>> +               itapdly << ITAPDLYSEL_SHIFT);
>>> +    regmap_update_bits(sdhci_am654->base, PHY_CTRL4,
>>> ITAPCHGWIN_MASK, 0);
>>> +}
>>> +
>>> +static void sdhci_am654_setup_dll(struct sdhci_host *host, unsigned
>>> int clock,
>>> +                  unsigned char timing)
>>>   {
>>>       struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>>       struct sdhci_am654_data *sdhci_am654 =
>>> sdhci_pltfm_priv(pltfm_host);
>>> @@ -236,17 +248,8 @@ static void sdhci_am654_setup_dll(struct
>>> sdhci_host *host, unsigned int clock)
>>>           dev_err(mmc_dev(host->mmc), "DLL failed to relock\n");
>>>           return;
>>>       }
>>> -}
>>> -static void sdhci_am654_write_itapdly(struct sdhci_am654_data
>>> *sdhci_am654,
>>> -                      u32 itapdly)
>>> -{
>>> -    /* Set ITAPCHGWIN before writing to ITAPDLY */
>>> -    regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPCHGWIN_MASK,
>>> -               1 << ITAPCHGWIN_SHIFT);
>>> -    regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPDLYSEL_MASK,
>>> -               itapdly << ITAPDLYSEL_SHIFT);
>>> -    regmap_update_bits(sdhci_am654->base, PHY_CTRL4,
>>> ITAPCHGWIN_MASK, 0);
>>> +    sdhci_am654_write_itapdly(sdhci_am654,
>>> sdhci_am654->itap_del_sel[timing]);
>>>   }
>>>   static void sdhci_am654_setup_delay_chain(struct sdhci_am654_data
>>> *sdhci_am654,
>>> @@ -298,7 +301,7 @@ static void sdhci_am654_set_clock(struct
>>> sdhci_host *host, unsigned int clock)
>>>       regmap_update_bits(sdhci_am654->base, PHY_CTRL4, mask, val);
>>>       if (timing > MMC_TIMING_UHS_SDR25 && clock >= CLOCK_TOO_SLOW_HZ) {
>>> -        sdhci_am654_setup_dll(host, clock);
>>> +        sdhci_am654_setup_dll(host, clock, timing);
>>>           sdhci_am654->dll_enable = true;
>>>       } else {
>>>           sdhci_am654_setup_delay_chain(sdhci_am654, timing);
>
>