Hello, I wanted to reduce CPU frequency to be less than 1 GHz. There is a similar question that someone asked a few years ago. https://community.nxp.com/t5/i-MX-Processors/Lower-CPU-frequency-on-imx8mm/td-p/955456. But the patch doesn't work for me. I am on imx-5.10.9-1.0.0.xml. The supported frequencies are 1.2, 1.6 and 1.8 GHz on imx8mm evk. How can I lower the cpu frequencies? Thanks.
detail steps please
For the L5.10.9-1.0.0 version BSP structure is not the same with the 4.9.98_2.0.0, so you can not use the patch you mentioned above. Add the 1 GHz node in the dts.
a53_opp_table: opp-table { compatible = "operating-points-v2"; opp-shared; opp-1200000000 { opp-hz = /bits/ 64 <1200000000>; opp-microvolt = <850000>; opp-supported-hw = <0xe>, <0x7>; clock-latency-ns = <150000>; opp-suspend; }; opp-1600000000 { opp-hz = /bits/ 64 <1600000000>; opp-microvolt = <950000>; opp-supported-hw = <0xc>, <0x7>; clock-latency-ns = <150000>; opp-suspend; }; opp-1800000000 { opp-hz = /bits/ 64 <1800000000>; opp-microvolt = <1000000>; opp-supported-hw = <0x8>, <0x3>; clock-latency-ns = <150000>; opp-suspend; }; };
Thanks for clarification. Is it possible to set the cpu frequency to 800M or 600 M or even lower speed? If possible, then how? Modify the app-table? Thanks.
Yes, the method is the same, you can try it.