mmc: sdhci-msm: Rectify DLL programming sequence

[PATCH v6 2/5] arm64: dts: qcom: Add sdhc dll-presets

Posted by Ram Prakash Gupta 1 month, 3 weeks ago

Add sdhc dll-presets for qdu1000 target.

Signed-off-by: Ram Prakash Gupta <quic_rampraka@quicinc.com>
---
 arch/arm64/boot/dts/qcom/qdu1000.dtsi | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/qdu1000.dtsi b/arch/arm64/boot/dts/qcom/qdu1000.dtsi
index 846e5e5899aa..bc31504d5c8c 100644
--- a/arch/arm64/boot/dts/qcom/qdu1000.dtsi
+++ b/arch/arm64/boot/dts/qcom/qdu1000.dtsi
@@ -912,8 +912,8 @@ sdhc: mmc@8804000 {
 
 			bus-width = <8>;
 
-			qcom,dll-config = <0x0007642c>;
-			qcom,ddr-config = <0x80040868>;
+			qcom,dll-presets = <0x000F64EC 0x0 0x01	0x2C010800 0x80040868>,
+					   <0x0007642C 0x0 0x10 0x2C010800 0x80040868>;
 
 			status = "disabled";
 
-- 
2.34.1

Re: [PATCH v6 2/5] arm64: dts: qcom: Add sdhc dll-presets

Posted by Krzysztof Kozlowski 1 month, 3 weeks ago

On 15/12/2025 13:00, Ram Prakash Gupta wrote:
> Add sdhc dll-presets for qdu1000 target.
> 
> Signed-off-by: Ram Prakash Gupta <quic_rampraka@quicinc.com>
> ---
>  arch/arm64/boot/dts/qcom/qdu1000.dtsi | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Please use subject prefixes matching the subsystem. You can get them for
example with `git log --oneline -- DIRECTORY_OR_FILE` on the directory
your patch is touching. For bindings, the preferred subjects are
explained here:
https://www.kernel.org/doc/html/latest/devicetree/bindings/submitting-patches.html#i-for-patch-submitters

> 
> diff --git a/arch/arm64/boot/dts/qcom/qdu1000.dtsi b/arch/arm64/boot/dts/qcom/qdu1000.dtsi
> index 846e5e5899aa..bc31504d5c8c 100644
> --- a/arch/arm64/boot/dts/qcom/qdu1000.dtsi
> +++ b/arch/arm64/boot/dts/qcom/qdu1000.dtsi
> @@ -912,8 +912,8 @@ sdhc: mmc@8804000 {
>  
>  			bus-width = <8>;
>  
> -			qcom,dll-config = <0x0007642c>;
> -			qcom,ddr-config = <0x80040868>;
> +			qcom,dll-presets = <0x000F64EC 0x0 0x01	0x2C010800 0x80040868>,
> +					   <0x0007642C 0x0 0x10 0x2C010800 0x80040868>;

That's non-bisectable. You just broke the users of this DTS. Also, case
change is not explained and your binding said nothing about deprecating
other properties.

Best regards,
Krzysztof

Re: [PATCH v6 2/5] arm64: dts: qcom: Add sdhc dll-presets

Posted by Krzysztof Kozlowski 1 month, 3 weeks ago

On 15/12/2025 13:05, Krzysztof Kozlowski wrote:
> On 15/12/2025 13:00, Ram Prakash Gupta wrote:
>> Add sdhc dll-presets for qdu1000 target.
>>
>> Signed-off-by: Ram Prakash Gupta <quic_rampraka@quicinc.com>
>> ---
>>  arch/arm64/boot/dts/qcom/qdu1000.dtsi | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> Please use subject prefixes matching the subsystem. You can get them for
> example with `git log --oneline -- DIRECTORY_OR_FILE` on the directory
> your patch is touching. For bindings, the preferred subjects are
> explained here:
> https://www.kernel.org/doc/html/latest/devicetree/bindings/submitting-patches.html#i-for-patch-submitters
> 
>>
>> diff --git a/arch/arm64/boot/dts/qcom/qdu1000.dtsi b/arch/arm64/boot/dts/qcom/qdu1000.dtsi
>> index 846e5e5899aa..bc31504d5c8c 100644
>> --- a/arch/arm64/boot/dts/qcom/qdu1000.dtsi
>> +++ b/arch/arm64/boot/dts/qcom/qdu1000.dtsi
>> @@ -912,8 +912,8 @@ sdhc: mmc@8804000 {
>>  
>>  			bus-width = <8>;
>>  
>> -			qcom,dll-config = <0x0007642c>;
>> -			qcom,ddr-config = <0x80040868>;
>> +			qcom,dll-presets = <0x000F64EC 0x0 0x01	0x2C010800 0x80040868>,
>> +					   <0x0007642C 0x0 0x10 0x2C010800 0x80040868>;
> 
> 
> That's non-bisectable. You just broke the users of this DTS. Also, case
> change is not explained and your binding said nothing about deprecating
> other properties.


Also, your binding said 10 items, not two.


Best regards,
Krzysztof

Re: [PATCH v6 2/5] arm64: dts: qcom: Add sdhc dll-presets

Posted by Ram Prakash Gupta 1 month, 3 weeks ago

On 12/15/2025 5:37 PM, Krzysztof Kozlowski wrote:
> On 15/12/2025 13:05, Krzysztof Kozlowski wrote:
>> On 15/12/2025 13:00, Ram Prakash Gupta wrote:
>>> Add sdhc dll-presets for qdu1000 target.
>>>
>>> Signed-off-by: Ram Prakash Gupta <quic_rampraka@quicinc.com>
>>> ---
>>>  arch/arm64/boot/dts/qcom/qdu1000.dtsi | 4 ++--
>>>  1 file changed, 2 insertions(+), 2 deletions(-)
>> Please use subject prefixes matching the subsystem. You can get them for
>> example with `git log --oneline -- DIRECTORY_OR_FILE` on the directory
>> your patch is touching. For bindings, the preferred subjects are
>> explained here:
>> https://www.kernel.org/doc/html/latest/devicetree/bindings/submitting-patches.html#i-for-patch-submitters

sure I missed to add qdu1000:, will add in subject.

>>> diff --git a/arch/arm64/boot/dts/qcom/qdu1000.dtsi b/arch/arm64/boot/dts/qcom/qdu1000.dtsi
>>> index 846e5e5899aa..bc31504d5c8c 100644
>>> --- a/arch/arm64/boot/dts/qcom/qdu1000.dtsi
>>> +++ b/arch/arm64/boot/dts/qcom/qdu1000.dtsi
>>> @@ -912,8 +912,8 @@ sdhc: mmc@8804000 {
>>>  
>>>  			bus-width = <8>;
>>>  
>>> -			qcom,dll-config = <0x0007642c>;
>>> -			qcom,ddr-config = <0x80040868>;
>>> +			qcom,dll-presets = <0x000F64EC 0x0 0x01	0x2C010800 0x80040868>,
>>> +					   <0x0007642C 0x0 0x10 0x2C010800 0x80040868>;
>>
>> That's non-bisectable. You just broke the users of this DTS. Also, case
>> change is not explained and your binding said nothing about deprecating
>> other properties.

right I will update the sequence of dt as last change in the series.

I couldn't get "case change is not explained" but I guess ask is for
explanation why is this change needed. As the soc is using artanis
dll, it needs to have 3 more register values as presets. So in total
2 arrays, for HS400 and HS200, are passed each having 5 elements,
DLL_CONFIG, DLL_CONFIG_2, DLL_CONFIG_3, DLL_USER_CTRL & DDR_CONFIG.
Without these sampling of data would not be optimal and might lead
to CRC errors.

The existing qcom,dll-config or qcom-ddr-config are not deprecated,
as upcoming soc could still be non-artanis and only dll-config and
ddr-config might be needed. But since it was added earlier in qdu1000,
removing it now as the code change is pushed into driver to support
dll-presets.

with QDU1000 there were instance of CRC errors and to fix dll-presets
is used instead of qcom,dll-config & qcom,ddr-config.

I will update the binding as well with more details.

>
> Also, your binding said 10 items, not two.
>
>
> Best regards,
> Krzysztof

Sorry I mistook the elements of array with Items. Will update in binding
to 2 items.

Re: [PATCH v6 2/5] arm64: dts: qcom: Add sdhc dll-presets

Posted by Krzysztof Kozlowski 1 month, 3 weeks ago

On 16/12/2025 13:41, Ram Prakash Gupta wrote:
> 
> On 12/15/2025 5:37 PM, Krzysztof Kozlowski wrote:
>> On 15/12/2025 13:05, Krzysztof Kozlowski wrote:
>>> On 15/12/2025 13:00, Ram Prakash Gupta wrote:
>>>> Add sdhc dll-presets for qdu1000 target.
>>>>
>>>> Signed-off-by: Ram Prakash Gupta <quic_rampraka@quicinc.com>
>>>> ---
>>>>  arch/arm64/boot/dts/qcom/qdu1000.dtsi | 4 ++--
>>>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>> Please use subject prefixes matching the subsystem. You can get them for
>>> example with `git log --oneline -- DIRECTORY_OR_FILE` on the directory
>>> your patch is touching. For bindings, the preferred subjects are
>>> explained here:
>>> https://www.kernel.org/doc/html/latest/devicetree/bindings/submitting-patches.html#i-for-patch-submitters
> 
> sure I missed to add qdu1000:, will add in subject.
> 
>>>> diff --git a/arch/arm64/boot/dts/qcom/qdu1000.dtsi b/arch/arm64/boot/dts/qcom/qdu1000.dtsi
>>>> index 846e5e5899aa..bc31504d5c8c 100644
>>>> --- a/arch/arm64/boot/dts/qcom/qdu1000.dtsi
>>>> +++ b/arch/arm64/boot/dts/qcom/qdu1000.dtsi
>>>> @@ -912,8 +912,8 @@ sdhc: mmc@8804000 {
>>>>  
>>>>  			bus-width = <8>;
>>>>  
>>>> -			qcom,dll-config = <0x0007642c>;
>>>> -			qcom,ddr-config = <0x80040868>;
>>>> +			qcom,dll-presets = <0x000F64EC 0x0 0x01	0x2C010800 0x80040868>,
>>>> +					   <0x0007642C 0x0 0x10 0x2C010800 0x80040868>;
>>>
>>> That's non-bisectable. You just broke the users of this DTS. Also, case
>>> change is not explained and your binding said nothing about deprecating
>>> other properties.
> 
> right I will update the sequence of dt as last change in the series.

This will fix nothing. Please read maintainer soc profile how DTS is
handled. It's still no go, shall I be explicit with NAK?

> 
> I couldn't get "case change is not explained" but I guess ask is for
> explanation why is this change needed. As the soc is using artanis

No, why are you making it upper case. What is the preferred style for DTS?


Best regards,
Krzysztof