Re: [PATCH 13/13] arm64: dts: allwinner: a100: Add CPU Operating Performance Points table

[Cody Eksal <masterr3c0rd@epochal.quest>]

On 2024/10/25 9:27 am, Andre Przywara wrote:
> On Thu, 24 Oct 2024 14:05:31 -0300
> Cody Eksal <masterr3c0rd@epochal.quest> wrote:
> 
>> From: Shuosheng Huang <huangshuosheng@allwinnertech.com>
>> 
>> Add an Operating Performance Points table for the CPU cores to
>> enable Dynamic Voltage & Frequency Scaling on the A100.
>> 
>> Signed-off-by: Shuosheng Huang <huangshuosheng@allwinnertech.com>
>> [masterr3c0rd@epochal.quest: fix typos in -cpu-opp, use compatible]
>> Signed-off-by: Cody Eksal <masterr3c0rd@epochal.quest>
>> ---
>>  .../allwinner/sun50i-a100-allwinner-perf1.dts |  5 ++
>>  .../dts/allwinner/sun50i-a100-cpu-opp.dtsi    | 90 
>> +++++++++++++++++++
>>  .../arm64/boot/dts/allwinner/sun50i-a100.dtsi |  8 ++
>>  3 files changed, 103 insertions(+)
>>  create mode 100644 
>> arch/arm64/boot/dts/allwinner/sun50i-a100-cpu-opp.dtsi
>> 
>> diff --git 
>> a/arch/arm64/boot/dts/allwinner/sun50i-a100-allwinner-perf1.dts 
>> b/arch/arm64/boot/dts/allwinner/sun50i-a100-allwinner-perf1.dts
>> index 29e9d24da8b6..99b1b2f7b92a 100644
>> --- a/arch/arm64/boot/dts/allwinner/sun50i-a100-allwinner-perf1.dts
>> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a100-allwinner-perf1.dts
>> @@ -6,6 +6,7 @@
>>  /dts-v1/;
>> 
>>  #include "sun50i-a100.dtsi"
>> +#include "sun50i-a100-cpu-opp.dtsi"
>> 
>>  #include <dt-bindings/gpio/gpio.h>
>> 
>> @@ -67,6 +68,10 @@ &usb_otg {
>>  	status = "okay";
>>  };
>> 
>> +&cpu0 {
>> +	cpu-supply = <&reg_dcdc2>;
>> +};
>> +
>>  &pio {
>>  	vcc-pb-supply = <&reg_dcdc1>;
>>  	vcc-pc-supply = <&reg_eldo1>;
>> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a100-cpu-opp.dtsi 
>> b/arch/arm64/boot/dts/allwinner/sun50i-a100-cpu-opp.dtsi
>> new file mode 100644
>> index 000000000000..eeb8d20f3fb4
>> --- /dev/null
>> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a100-cpu-opp.dtsi
>> @@ -0,0 +1,90 @@
>> +// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
>> +// Copyright (c) 2020 Yangtao Li <frank@allwinnertech.com>
>> +// Copyright (c) 2020 ShuoSheng Huang 
>> <huangshuosheng@allwinnertech.com>
>> +
>> +/ {
>> +	cpu_opp_table: cpu-opp-table {
>> +		compatible = "allwinner,sun50i-a100-operating-points";
>> +		nvmem-cells = <&cpu_speed_grade>;
>> +		opp-shared;
>> +
>> +		opp@408000000 {
>> +			clock-latency-ns = <244144>; /* 8 32k periods */
>> +			opp-hz = /bits/ 64 <408000000>;
>> +
>> +			opp-microvolt-speed0 = <900000 900000 1200000>;
>> +			opp-microvolt-speed1 = <900000 900000 1200000>;
>> +			opp-microvolt-speed2 = <900000 900000 1200000>;
> 
> Is there actually an advantage when using the three cells version?
> I wonder if we should go with just the target voltage (the first cell
> here), as done for the H616.
It probably makes sense to follow precedent; I've updated V2 to make 
these single-cell.
> Apart from that it looks fine to me.
I did get a comment from Rob's bot that picked up some issues with the 
namings of these nodes; I've updated that as well.

Thanks!
- Cody
> Cheers,
> Andre.
> 
>> +		};
>> +
>> +		opp@600000000 {
>> +			clock-latency-ns = <244144>; /* 8 32k periods */
>> +			opp-hz = /bits/ 64 <600000000>;
>> +
>> +			opp-microvolt-speed0 = <900000 900000 1200000>;
>> +			opp-microvolt-speed1 = <900000 900000 1200000>;
>> +			opp-microvolt-speed2 = <900000 900000 1200000>;
>> +		};
>> +
>> +		opp@816000000 {
>> +			clock-latency-ns = <244144>; /* 8 32k periods */
>> +			opp-hz = /bits/ 64 <816000000>;
>> +
>> +			opp-microvolt-speed0 = <940000 940000 1200000>;
>> +			opp-microvolt-speed1 = <900000 900000 1200000>;
>> +			opp-microvolt-speed2 = <900000 900000 1200000>;
>> +		};
>> +
>> +		opp@1080000000 {
>> +			clock-latency-ns = <244144>; /* 8 32k periods */
>> +			opp-hz = /bits/ 64 <1080000000>;
>> +
>> +			opp-microvolt-speed0 = <1020000 1020000 1200000>;
>> +			opp-microvolt-speed1 = <980000 980000 1200000>;
>> +			opp-microvolt-speed2 = <950000 950000 1200000>;
>> +		};
>> +
>> +		opp@1200000000 {
>> +			clock-latency-ns = <244144>; /* 8 32k periods */
>> +			opp-hz = /bits/ 64 <1200000000>;
>> +
>> +			opp-microvolt-speed0 = <1100000 1100000 1200000>;
>> +			opp-microvolt-speed1 = <1020000 1020000 1200000>;
>> +			opp-microvolt-speed2 = <1000000 1000000 1200000>;
>> +		};
>> +
>> +		opp@1320000000 {
>> +			clock-latency-ns = <244144>; /* 8 32k periods */
>> +			opp-hz = /bits/ 64 <1320000000>;
>> +
>> +			opp-microvolt-speed0 = <1160000 1160000 1200000>;
>> +			opp-microvolt-speed1 = <1060000 1060000 1200000>;
>> +			opp-microvolt-speed2 = <1030000 1030000 1200000>;
>> +		};
>> +
>> +		opp@1464000000 {
>> +			clock-latency-ns = <244144>; /* 8 32k periods */
>> +			opp-hz = /bits/ 64 <1464000000>;
>> +
>> +			opp-microvolt-speed0 = <1180000 1180000 1200000>;
>> +			opp-microvolt-speed1 = <1180000 1180000 1200000>;
>> +			opp-microvolt-speed2 = <1130000 1130000 1200000>;
>> +		};
>> +	};
>> +};
>> +
>> +&cpu0 {
>> +	operating-points-v2 = <&cpu_opp_table>;
>> +};
>> +
>> +&cpu1 {
>> +	operating-points-v2 = <&cpu_opp_table>;
>> +};
>> +
>> +&cpu2 {
>> +	operating-points-v2 = <&cpu_opp_table>;
>> +};
>> +
>> +&cpu3 {
>> +	operating-points-v2 = <&cpu_opp_table>;
>> +};
>> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a100.dtsi 
>> b/arch/arm64/boot/dts/allwinner/sun50i-a100.dtsi
>> index 6dca766ea222..747a0292ef98 100644
>> --- a/arch/arm64/boot/dts/allwinner/sun50i-a100.dtsi
>> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a100.dtsi
>> @@ -23,6 +23,7 @@ cpu0: cpu@0 {
>>  			device_type = "cpu";
>>  			reg = <0x0>;
>>  			enable-method = "psci";
>> +			clocks = <&ccu CLK_CPUX>;
>>  		};
>> 
>>  		cpu1: cpu@1 {
>> @@ -30,6 +31,7 @@ cpu1: cpu@1 {
>>  			device_type = "cpu";
>>  			reg = <0x1>;
>>  			enable-method = "psci";
>> +			clocks = <&ccu CLK_CPUX>;
>>  		};
>> 
>>  		cpu2: cpu@2 {
>> @@ -37,6 +39,7 @@ cpu2: cpu@2 {
>>  			device_type = "cpu";
>>  			reg = <0x2>;
>>  			enable-method = "psci";
>> +			clocks = <&ccu CLK_CPUX>;
>>  		};
>> 
>>  		cpu3: cpu@3 {
>> @@ -44,6 +47,7 @@ cpu3: cpu@3 {
>>  			device_type = "cpu";
>>  			reg = <0x3>;
>>  			enable-method = "psci";
>> +			clocks = <&ccu CLK_CPUX>;
>>  		};
>>  	};
>> 
>> @@ -142,6 +146,10 @@ efuse@3006000 {
>>  			ths_calibration: calib@14 {
>>  				reg = <0x14 8>;
>>  			};
>> +
>> +			cpu_speed_grade: cpu-speed-grade@1c {
>> +				reg = <0x1c 0x2>;
>> +			};
>>  		};
>> 
>>  		watchdog@30090a0 {