i.MX 8M Plus PMIC usage

[www1519]

Hi! NXP Engineer

In my design, IMX8M Plus+PCA9450C+LPDDR4(refer to NXP EVK) is used.

Now , I want to reduce the working frequency of SOC and LPDDR4,

but the frequencis file is not visible with cat command, can not to be read and edited.

(If use NXP EVK, the frequencis file is visible with cat command, can be to read and edited.)

why is it,   can you tell me?

The difference between my design and the NXP EVK circuit is as follows.

NXP EVK: PCA9450C pin 13(IRQ_B) is connected to SoC pin D6(GPIO1_IO03)

My design: PCA9450C pin 13(IRQ_B) w/100k PU is connected to SoC pin AJ16(SAI2_RXC)

Note: The voltage of Soc SAI2 is design with 1.8V and connected to PCA9450C BUCK5. 

Confirm it please.

Thanks a lot

Best regarads.

[www1519]

Hi @Dhruvit 

I'm very sorry for the late reply.

the above problem has been solved.

Thank you for support.

Best regard!

[Dhruvit]

Hi @www1519,

I hope you are doing well.

Please make sure that below mentioned options are enabled in kernel options : 

CONFIG_CPU_FREQ=y

CONFIG_ARM_IMX_CPUFREQ_DT=y

Please provide me with debug logs , device tree file and commands used for further debugging.

Please make sure that you have made changes in pinctrl and interrupts property corresponding to IRQ_B pin connection change.

Thanks & Regards,
Dhruvit Vasavada