i.MX ProcessorsのトピックRe: i.mx8mp cpufreq setting about reducing power comsumption

i.mx8mp cpufreq setting about reducing power comsumption

rockylee — Wed, 17 May 2023 11:38:40 GMT

1 、Basic information :

i.mx8mp ，Linux5.10.35, Yocto hardknott 。

i.mx8mp is designed as data acquisition devices .

2、Qustion:

How to extend i.mx8mp cpufreq setting in imx8mp.dtsi for reducing cpu temperature ?

Desired cpufreq setting: 600MHz、800Mhz 、1GHz 。

How to set i.mx8mp voltage with different frequces ?

3、Present situation

The devices temperature is very high and i.mx8mp is difficult to touch .

i.mx8mp frequces is 1.2G hz and 1.6Hz described as follow .

The cpufreq setting in imx8mp.dtsi only has three parts , described as follow

a53_opp_table: opp-table {
compatible = "operating-points-v2";
opp-shared;

opp-1200000000 {
opp-hz = /bits/ 64 <1200000000>;
opp-microvolt = <850000>;
opp-supported-hw = <0x8a0>, <0x7>;
clock-latency-ns = <150000>;
opp-suspend;
};

opp-1600000000 {
opp-hz = /bits/ 64 <1600000000>;
opp-microvolt = <950000>;
opp-supported-hw = <0xa0>, <0x7>;
clock-latency-ns = <150000>;
opp-suspend;
};

opp-1800000000 {
opp-hz = /bits/ 64 <1800000000>;
opp-microvolt = <1000000>;
opp-supported-hw = <0x20>, <0x3>;
clock-latency-ns = <150000>;
opp-suspend;
};
}.

Re: i.mx8mp cpufreq setting about reducing power comsumption

Sanket_Parekh — Thu, 18 May 2023 13:49:54 GMT

Hi @rockylee

I hope you are doing well

One can add the opp-entries in the device tree opp-table to choose the frequency,

For the supported frequency please refer to the Table 25. PLL electrical parameters from the datasheet. For ARM_PLL it is between 800 MHz to 1800 MHz.

For the voltage-related information, kindly refer to section 3.1.4 Operating ranges from the datasheet and section 3.2.1 VDD voltage levels - Table 2 from i.MX 8M Plus Power Consumption Measurement

To reduce power consumption, kindly refer to section 3.10 Unused input/output terminations from the i.MX 8M Plus Hardware Developer’s Guide

I hope this information helps you.

Thanks & Regards

Sanket Parekh

Re: i.mx8mp cpufreq setting about reducing power comsumption

mengfei — Mon, 13 Nov 2023 06:21:41 GMT

when cpufreq is 800Mhz，voltage is what? 3.2.1 VDD voltage levels only describe three voltage