[IMX6duallite] lower the core frequency to 396MHz

[Roger_C]

Hey everyone ,

I have questions about the IMX6dualite component to lower the core frequency to 396MHz .

According to the AN4576, I can operate at a frequency of 396MHz. For that it would be necessary that VDD_ARM_CAP is a voltage at 0.95V and VDD_SOC_CAP/VDD_PU_CAP is at 1.175V. 

From what I understand, the voltages VDD_ARM_CAP, VDD_SOC_CAP & VDD_PU_CAP are provided internally and that an external power supply is provided on VDD_ARM_IN and VDD_SOC_IN.   

How can I achieve this wiring to reach the 396MHz frequency?

 Thank you for your help, 

Regards

Roger Crane / Junior System Engineer

[Roger_C]

Hello BiyongSUN,

thank you for your feedback.

Your answer was very helpful.

Regards,

Roger_C

[BiyongSUN · Accepted solution]

NXP  linux BSP already enable DVFS.

You can  use userspace governor in userspace to force the frequency including 396M. 

And operation points set in dts 

lf-5.10.35-2.0.0\linux-imx\arch\arm\boot\dts\imx6dl.dtsi

cpus {
#address-cells = <1>;
#size-cells = <0>;

cpu0: cpu@0 {
compatible = "arm,cortex-a9";
device_type = "cpu";
reg = <0>;
next-level-cache = <&L2>;
operating-points = <
/* kHz uV */
996000 1250000
792000 1175000
396000 1150000
>;
fsl,soc-operating-points = <
/* ARM kHz SOC-PU uV */
996000 1175000
792000 1175000
396000 1175000
>;