How do i get cpu frequency in imx8mm?

takeshi100 — Wed, 17 Jul 2024 10:27:41 GMT

Hi.

I can't get cpu frequency on imx8mm with /proc/cpuinfo etc.

How do i get it?

■conditions
BSP = i.MX Linux Yocto Project BSP 6.1.55_2.2.0
image = image based core-image-full-cmdline-imx8mm-lpddr4-evk
hardware = custom board with imx8mm

■log(cpu info)

root@XXX:~# cpufreq-info

cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009

Report errors and bugs to cpufreq@vger.kernel.org, please.

analyzing CPU 0:

no or unknown cpufreq driver is active on this CPU

analyzing CPU 1:

no or unknown cpufreq driver is active on this CPU

analyzing CPU 2:

no or unknown cpufreq driver is active on this CPU

analyzing CPU 3:

no or unknown cpufreq driver is active on this CPU

root@XXX:~# cat /proc/cpuinfo

processor : 0

BogoMIPS : 16.00

Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid

CPU implementer : 0x41

CPU architecture: 8

CPU variant : 0x0

CPU part : 0xd03

CPU revision : 4

processor : 1

BogoMIPS : 16.00

Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid

CPU implementer : 0x41

CPU architecture: 8

CPU variant : 0x0

CPU part : 0xd03

CPU revision : 4

processor : 2

BogoMIPS : 16.00

Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid

CPU implementer : 0x41

CPU architecture: 8

CPU variant : 0x0

CPU part : 0xd03

CPU revision : 4

processor : 3

BogoMIPS : 16.00

Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid

CPU implementer : 0x41

CPU architecture: 8

CPU variant : 0x0

CPU part : 0xd03

CPU revision : 4

root@XXX:~# lscpu

Architecture: aarch64

CPU op-mode(s): 32-bit, 64-bit

Byte Order: Little Endian

CPU(s): 4

On-line CPU(s) list: 0-3

Vendor ID: ARM

Model name: Cortex-A53

Model: 4

Thread(s) per core: 1

Core(s) per cluster: 4

Socket(s): -

Cluster(s): 1

Stepping: r0p4

BogoMIPS: 16.00

Flags: fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid

Caches (sum of all):

L1d: 128 KiB (4 instances)

L1i: 128 KiB (4 instances)

L2: 512 KiB (1 instance)

NUMA:

NUMA node(s): 1

NUMA node0 CPU(s): 0-3

Vulnerabilities:

Gather data sampling: Not affected

Itlb multihit: Not affected

L1tf: Not affected

Mds: Not affected

Meltdown: Not affected

Mmio stale data: Not affected

Retbleed: Not affected

Spec rstack overflow: Not affected

Spec store bypass: Not affected

Spectre v1: Mitigation; __user pointer sanitization

Spectre v2: Not affected

Srbds: Not affected

Tsx async abort: Not affected

■log(kernel config)

root@XXX:~# zcat /proc/config.gz | grep CPU_FREQ

CONFIG_CPU_FREQ=y

CONFIG_CPU_FREQ_GOV_ATTR_SET=y

CONFIG_CPU_FREQ_GOV_COMMON=y

CONFIG_CPU_FREQ_STAT=y

# CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE is not set

# CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE is not set

# CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE is not set

CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y

# CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE is not set

# CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL is not set

CONFIG_CPU_FREQ_GOV_PERFORMANCE=y

CONFIG_CPU_FREQ_GOV_POWERSAVE=y

CONFIG_CPU_FREQ_GOV_USERSPACE=y

CONFIG_CPU_FREQ_GOV_ONDEMAND=y

CONFIG_CPU_FREQ_GOV_CONSERVATIVE=y

CONFIG_CPU_FREQ_GOV_SCHEDUTIL=y

CONFIG_CPU_FREQ_THERMAL=y

root@XXX:~# zcat /proc/config.gz | grep CPUFREQ
CONFIG_CPUFREQ_DT=y
CONFIG_CPUFREQ_DT_PLATDEV=y
CONFIG_ACPI_CPPC_CPUFREQ=m
CONFIG_ACPI_CPPC_CPUFREQ_FIE=y
CONFIG_ARM_SCPI_CPUFREQ=y
CONFIG_ARM_IMX_CPUFREQ_DT=y
CONFIG_ARM_SCMI_CPUFREQ=y
CONFIG_QORIQ_CPUFREQ=y

Re: How do i get cpu frequency in imx8mm?

Chavira — Wed, 17 Jul 2024 19:08:25 GMT

Hi @takeshi100!

Thank you for contacting NXP Support!

The command should be:

cat /sys/devices/system/cpu/*/cpufreq/cpuinfo_cur_freq

You can see all the available options in our Linux User Guide on chapter "6.2 CPU frequency scaling"

https://www.nxp.com/docs/en/user-guide/IMX_LINUX_USERS_GUIDE.pdf

Best Regards!

Chavira

Re: How do i get cpu frequency in imx8mm?

takeshi100 — Thu, 18 Jul 2024 01:59:55 GMT

Hi, Chavira.

Thanks for replying.

There aren't cpufreq directories.
Is there anything I need to configure?

■log

root@XXX:~# ls /sys/devices/system/cpu/cpu0/
cache cpu_capacity cpuidle crash_notes crash_notes_size hotplug node0 of_node online power regs subsystem topology uevent

Best Regards.

Re: How do i get cpu frequency in imx8mm?

takeshi100 — Thu, 18 Jul 2024 10:04:14 GMT

I resolved this problem by fixing device tree.

Pending of cpufreq-dt was happend.
The cause of it was incorrect configuration of the PMIC in device tree.
The PMIC of the custom board and evk are different, and the I2C line to which they belong is also different.

■log
root@XXX:~# journalctl -b | grep cpufreq
Mar 03 09:49:19 XXX kernel: imx-cpufreq-dt imx-cpufreq-dt: cpu speed grade 3 mkt segment 0 supported-hw 0x8 0x1
Mar 03 11:38:17 XXX kernel: platform cpufreq-dt: deferred probe pending

■reference
・https://www.reddit.com/r/linux4noobs/comments/1brkjja/trying_to_get_cpufreqdt_functioning_on_arm/
・https://community.nxp.com/t5/i-MX-Processors/How-to-enable-cpufreq-in-Linux-imx8mmevk-5-10-35-lts-Hardknott/m-p/1328032/highlight/true?profile.language=ja

topic Re: How do i get cpu frequency in imx8mm? in i.MX Processors

How do i get cpu frequency in imx8mm?

Re: How do i get cpu frequency in imx8mm?

Re: How do i get cpu frequency in imx8mm?

Re: How do i get cpu frequency in imx8mm?