Re: [PATCH v8 5/7] arm64: dts: qcom: sm8450: Add opp table support to PCIe

[Manivannan Sadhasivam <mani@kernel.org>]

On Sat, Mar 02, 2024 at 09:29:59AM +0530, Krishna chaitanya chundru wrote:
> PCIe needs to choose the appropriate performance state of RPMH power
> domain and interconnect bandwidth based up on the PCIe gen speed.
> 
> Add the OPP table support to specify RPMH performance states and
> interconnect peak bandwidth.
> 
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
> ---
>  arch/arm64/boot/dts/qcom/sm8450.dtsi | 74 ++++++++++++++++++++++++++++++++++++
>  1 file changed, 74 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sm8450.dtsi b/arch/arm64/boot/dts/qcom/sm8450.dtsi
> index 6b1d2e0d9d14..662f2129f20d 100644
> --- a/arch/arm64/boot/dts/qcom/sm8450.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sm8450.dtsi
> @@ -1827,7 +1827,32 @@ pcie0: pcie@1c00000 {
>  			pinctrl-names = "default";
>  			pinctrl-0 = <&pcie0_default_state>;
>  
> +			operating-points-v2 = <&pcie0_opp_table>;
> +
>  			status = "disabled";
> +
> +			pcie0_opp_table: opp-table {
> +				compatible = "operating-points-v2";
> +
> +				opp-2500000 {

Add the comments that you added below.

> +					opp-hz = /bits/ 64 <2500000>;
> +					required-opps = <&rpmhpd_opp_low_svs>;
> +					opp-peak-kBps = <250000 1>;

Isn't the peak bw should be greater that the avg bw? Atleast in upstream we
follow that pattern.

- Mani

> +				};
> +
> +				opp-5000000 {
> +					opp-hz = /bits/ 64 <5000000>;
> +					required-opps = <&rpmhpd_opp_low_svs>;
> +					opp-peak-kBps = <500000 1>;
> +				};
> +
> +				opp-8000000 {
> +					opp-hz = /bits/ 64 <8000000>;
> +					required-opps = <&rpmhpd_opp_nom>;
> +					opp-peak-kBps = <984500 1>;
> +				};
> +			};
> +
>  		};
>  
>  		pcie0_phy: phy@1c06000 {
> @@ -1938,7 +1963,56 @@ pcie1: pcie@1c08000 {
>  			pinctrl-names = "default";
>  			pinctrl-0 = <&pcie1_default_state>;
>  
> +			operating-points-v2 = <&pcie1_opp_table>;
> +
>  			status = "disabled";
> +
> +			pcie1_opp_table: opp-table {
> +				compatible = "operating-points-v2";
> +
> +				/* GEN 1x1 */
> +				opp-2500000 {
> +					opp-hz = /bits/ 64 <2500000>;
> +					required-opps = <&rpmhpd_opp_low_svs>;
> +					opp-peak-kBps = <250000 1>;
> +				};
> +
> +				/* GEN 1x2 GEN 2x1 */
> +				opp-5000000 {
> +					opp-hz = /bits/ 64 <5000000>;
> +					required-opps = <&rpmhpd_opp_low_svs>;
> +					opp-peak-kBps = <500000 1>;
> +				};
> +
> +				/* GEN 2x2 */
> +				opp-10000000 {
> +					opp-hz = /bits/ 64 <10000000>;
> +					required-opps = <&rpmhpd_opp_low_svs>;
> +					opp-peak-kBps = <1000000 1>;
> +				};
> +
> +				/* GEN 3x1 */
> +				opp-8000000 {
> +					opp-hz = /bits/ 64 <8000000>;
> +					required-opps = <&rpmhpd_opp_nom>;
> +					opp-peak-kBps = <984500 1>;
> +				};
> +
> +				/* GEN 3x2 GEN 4x1 */
> +				opp-16000000 {
> +					opp-hz = /bits/ 64 <16000000>;
> +					required-opps = <&rpmhpd_opp_nom>;
> +					opp-peak-kBps = <1969000 1>;
> +				};
> +
> +				/* GEN 4x2 */
> +				opp-32000000 {
> +					opp-hz = /bits/ 64 <32000000>;
> +					required-opps = <&rpmhpd_opp_nom>;
> +					opp-peak-kBps = <3938000 1>;
> +				};
> +			};
> +
>  		};
>  
>  		pcie1_phy: phy@1c0e000 {
> 
> -- 
> 2.42.0
> 

-- 
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