Re: [PATCH v6 4/5] mmc: sdhci-msm: Add Device tree parsing logic for DLL settings

Ram Prakash Gupta
2025-12-18T11:32:29Z

On 12/16/2025 7:59 PM, Konrad Dybcio wrote:
> On 12/15/25 1:00 PM, Ram Prakash Gupta wrote:
>> From: Sachin Gupta <quic_sachgupt@quicinc.com>
>>
>> This update introduces the capability to configure HS200
>> and HS400 DLL settings via the device tree and parsing it.
>>
>> Signed-off-by: Sachin Gupta <quic_sachgupt@quicinc.com>
>> Signed-off-by: Ram Prakash Gupta <quic_rampraka@quicinc.com>
>> ---
> [...]
>
>> +#define DLL_SIZE 10
>> +static int sdhci_msm_dt_parse_dll_info(struct device *dev, struct sdhci_msm_host *msm_host)
>> +{
>> + u32 *dll_table = &msm_host->dll[0].dll_config;
>> + int ret;
>> +
>> + msm_host->artanis_dll = false;
>> +
>> + ret = of_property_read_variable_u32_array(dev->of_node,
>> + "qcom,dll-presets",
>> + dll_table, DLL_SIZE, DLL_SIZE);
>> + if (ret == DLL_SIZE)
>> + msm_host->artanis_dll = true;
> This feels backwards.. can we first somehow determine whether this
> platform has the artanis_dll (whatever that is since you didn't explain)
> and then make decisions on what to retrieve from the DT & how to
> interpret it?

I checked document and with hardware designers, currently there is no
distinguishable hardware configuration which can be used, will have to
rely on dt only.

>
>> + return ret;
>> +}
>> +
>> static int sdhci_msm_probe(struct platform_device *pdev)
>> {
>> struct sdhci_host *host;
>> @@ -2580,6 +2612,15 @@ static int sdhci_msm_probe(struct platform_device *pdev)
>>
>> msm_host->saved_tuning_phase = INVALID_TUNING_PHASE;
>>
>> + /*
>> + * Parse HSR dll only when property is present in DT.
>> + */
> /* Parse ... */, it's short enough
>
> Probably also "DLL"
>
> Konrad

sure, will update.

Thanks,
Ram