[PATCH v3 2/3] arm64: dts: qcom: qcs615: add UFS node

[Xin Liu]

在 2024/12/6 5:21, Konrad Dybcio 写道:
> On 22.11.2024 7:44 AM, Xin Liu wrote:
>> From: Sayali Lokhande <quic_sayalil at quicinc.com>
>>
>> Add the UFS Host Controller node and its PHY for QCS615 SoC.
>>
>> Signed-off-by: Sayali Lokhande <quic_sayalil at quicinc.com>
>> Co-developed-by: Xin Liu <quic_liuxin at quicinc.com>
>> Signed-off-by: Xin Liu <quic_liuxin at quicinc.com>
>> ---
> 
> [...]
> 
>> +
>> +			operating-points-v2 = <&ufs_opp_table>;
>> +			interconnects = <&aggre1_noc MASTER_UFS_MEM QCOM_ICC_TAG_ALWAYS
>> +					 &mc_virt SLAVE_EBI1 QCOM_ICC_TAG_ALWAYS>,
>> +					<&gem_noc MASTER_APPSS_PROC QCOM_ICC_TAG_ALWAYS
>> +					 &config_noc SLAVE_UFS_MEM_CFG QCOM_ICC_TAG_ALWAYS>;
> 
> QCOM_ICC_TAG_ACTIVE_ONLY for the cpu path
I need to ask you for advice. I have reviewed the ufs_mem_hc of many 
devices and found that all of them use QCOM_ICC_TAG_ALWAYS for their 
interconnects cpu path. Why do I need to use QCOM_ICC_TAG_ACTIVE_ONLY here?
> 
>> +			interconnect-names = "ufs-ddr",
>> +					     "cpu-ufs";
>> +
>> +			power-domains = <&gcc UFS_PHY_GDSC>;
>> +			required-opps = <&rpmhpd_opp_nom>;
> 
> this contradicts the levels in the OPP table:
The required-opps here corresponds to opp-200000000 in the opp_table 
below. Similarly, I referred to sm8550.dtsi, whose required-opps also 
corresponds to the opp table.
> 
>> +
>> +			iommus = <&apps_smmu 0x300 0x0>;
>> +			dma-coherent;
>> +
>> +			lanes-per-direction = <1>;
>> +
>> +			phys = <&ufs_mem_phy>;
>> +			phy-names = "ufsphy";
>> +
>> +			#reset-cells = <1>;
>> +
>> +			status = "disabled";
>> +
>> +			ufs_opp_table: opp-table {
>> +				compatible = "operating-points-v2";
>> +
>> +				opp-50000000 {
>> +					opp-hz = /bits/ 64 <50000000>,
>> +						 /bits/ 64 <0>,
>> +						 /bits/ 64 <0>,
>> +						 /bits/ 64 <37500000>,
>> +						 /bits/ 64 <75000000>,
>> +						 /bits/ 64 <0>,
>> +						 /bits/ 64 <0>,
>> +						 /bits/ 64 <0>;
>> +					required-opps = <&rpmhpd_opp_low_svs>;
>> +				};
>> +
> 
> Konrad