Use of Powertop with imx8 processor

I want to use power management tool Power-top using apalis imx8 on ixora carrier board but it is not showing cores utilization as i have attached screenshot . So i just want to know whether power top tool is compatible with apalis imx8 module and if it is compatible then what are the steps to be followed.

Hi @milanpreetkaur,

Checking the PowerTop Source Code, there are some kernel configurations dependencies that need to be enabled:

CONFIG_NO_HZ
CONFIG_HIGH_RES_TIMERS
CONFIG_HPET_TIMER
CONFIG_CPU_FREQ_GOV_ONDEMAND
CONFIG_USB_SUSPEND
CONFIG_SND_AC97_POWER_SAVE
CONFIG_TIMER_STATS
CONFIG_PERF_EVENTS
CONFIG_PERF_COUNTERS
CONFIG_TRACEPOINTS
CONFIG_TRACING
CONFIG_EVENT_POWER_TRACING_DEPRECATED
CONFIG_X86_MSR
ACPI_PROCFS_POWER
CONFIG_DEBUG_FS

Could you please try to enable them and check if it works or not?

These articles will help you:

Best Regards,
Hiago.

Hi
As you have suggested me to enable kernel dependencies for enabling power top on IMX8 board. So i have checked kernel dependencies and list is mentioned below. Some of the dependencies not found as mentioned in below list.

CONFIG_NO_HZ    --not set --- (enabled)
CONFIG_HIGH_RES_TIMERS---already set
CONFIG_HPET_TIMER---**(not found)**
CONFIG_CPU_FREQ_GOV_ONDEMAND--already set
CONFIG_USB_SUSPEND---**(not found)**
CONFIG_SND_AC97_POWER_SAVE--**(not found)**
CONFIG_TIMER_STATS---**(not found)**
CONFIG_PERF_EVENTS--enabled
CONFIG_PERF_COUNTERS---**(not found)**
CONFIG_TRACEPOINTS---**(not found)**
CONFIG_TRACING--already enabled
CONFIG_EVENT_POWER_TRACING_DEPRECATED---**(not found)**
CONFIG_X86_MSR---**(not found)**
ACPI_PROCFS_POWER---**(not found)**
CONFIG_DEBUG_FS-- already enabled 

So please suggest me some other way or how can we write dependency if some dependency is not found in kernel config file?

Hi @milanpreetkaur,

Could you try to enable those that are available and check if it works or not?

The README from the powertop source code seems to be outdated, so maybe some kernel configs are not available. I suggested you use the kernel menu config instead of editing this file manually, so all dependencies will be added aswell.

Best Regards,
Hiago.

Hi Hiago

I didn’t edit the file manually , used the kernel menu config for enabling dependencies. As i have enabled some dependency and rebuilded image as well as tested the power top on my board it doesn’t works. So please suggest me some other way as i have also send some of the dependencies are not present in kernel config or to write dependency

Hi @milanpreetkaur,

Ok, so probably the powertop is not supported yet for NXP iMX8 processors.
The only link I found about this in the NXP community is about the iMX6 processor: Powertop for Linux / Android - NXP Community

However, it seems that this tool doesn’t support iMX6 as well.

Best Regards,
Hiago.

Hi Hiago

Thanks for the reply
Can you tell me which tool you are using if you want to measure the power of cores in imx8 processor ?As you have mentioned power optimization for imx8 processor which tool you have used or core power measurement

Hi @milanpreetkaur,

Right now I don’t recall any measurement individually for each core. We have some test measurements of the current that is going to the module in heavy loads, with all the cores in general.

I will suggest you take a look at these two developer articles:

Hope this helps you to get more information about power and our modules.

Best Regards,
Hiago.