Re: [PATCH V3 1/4] dt-bindings: mmc: Add dll-hsr-list for HS400 and HS200 modes

From: Konrad Dybcio
Date: Fri Jun 27 2025 - 09:58:21 EST


On 6/26/25 7:42 PM, Krzysztof Kozlowski wrote:
> On 26/06/2025 16:16, Ram Prakash Gupta wrote:
>> On 1/22/2025 3:56 PM, Krzysztof Kozlowski wrote:
>>> On 22/01/2025 10:47, Sachin Gupta wrote:
>>>> Document the 'dll-hsr-list' property for MMC device tree bindings.
>>>> The 'dll-hsr-list' property defines the DLL configurations for HS400
>>>> and HS200 modes.
>>>>
>>>> Signed-off-by: Sachin Gupta <quic_sachgupt@xxxxxxxxxxx>
>>>> ---
>>>> Documentation/devicetree/bindings/mmc/sdhci-msm.yaml | 5 +++++
>>>> 1 file changed, 5 insertions(+)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/mmc/sdhci-msm.yaml b/Documentation/devicetree/bindings/mmc/sdhci-msm.yaml
>>>> index 8b393e26e025..65dc3053df75 100644
>>>> --- a/Documentation/devicetree/bindings/mmc/sdhci-msm.yaml
>>>> +++ b/Documentation/devicetree/bindings/mmc/sdhci-msm.yaml
>>>> @@ -133,6 +133,11 @@ properties:
>>>> $ref: /schemas/types.yaml#/definitions/uint32
>>>> description: platform specific settings for DLL_CONFIG reg.
>>>>
>>>> + qcom,dll-hsr-list:
>>>> + maxItems: 10
>>>> + $ref: /schemas/types.yaml#/definitions/uint32
>>> uint32 has only one item. Anyway, there is already DLL there, so don't
>>> duplicate or explain why this is different. Explain also why this is not
>>> deducible from the compatible.
>>
>
>
> Timeline still amazes me. I will be grumpy on this thread.
>
>> I will change it to reflect array from uint32.
>> There is change with artanis DLL hw addition where it need total of 5 entries
>> (dll_config, dll_config_2, dll_config_3, dll_usr_ctl, ddr_config)
>> for each HS400 and HS200 modes, hence the new addition in dt. And these values
>> are not fixed and varies for every SoC, hence this needs to be passed through
>> dt like it was passed earlier for qcom,dll-config & qcom,ddr-config.
>
>
> Eh, no. That's not a valid reason. It's still SoC deducible. Don't bring
> your downstream practices here, but remove EVERYTHING from downstream
> and start doing things like upstream is doing.

QC SoCs have between 0 and 4 SDHCI instances, each one potentially requiring
different tuning, let's keep this data in DT

Konrad