Hi, Experts
below is imx6ull evk's Schematic
GPIO_DVFS & PMIC_STBY_REQ are used to select the voltage of VDD_ARM_SOC_IN. As i know PMIC_STBY_REQ is the dedicated pin, but i do know where and how this GPIO_DVFS is used in imx6ull BSP's kernel? and i can't even find out any description in dts?
Any suggest is appreciated!
Hi changbao
one can check description in sect.2.5.3 CPU Frequency Scaling (CPUFREQ)
Linux Manual included in Linux 4.19.35_1.1.0 Documentation
Best regards
igor
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------
Hi igorpadykov
Think you for your reply.
I have read through the Chapter 2.5.3 CPU Frequency Scaling (CPUFREQ) , but it do not answer my question. As i know GPIO_DVFS is a gpio, so i think this gpio must be controlled by a driver in somewhere in the kernel. So my question is how can i find this driver and code related to GPIO_DVFS?
BTW:
i noticed someone post in this community
https://community.nxp.com/message/1246207?commentID=1246207#comment-1246207
reg_gpio_dvfs: regulator-gpio {
compatible = "regulator-gpio";
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_dvfs>;
regulator-min-microvolt = <1300000>;
regulator-max-microvolt = <1400000>;
regulator-name = "gpio_dvfs";
regulator-type = "voltage";
gpios = <&gpio5 3 GPIO_ACTIVE_HIGH>; /* This gpio match the GPIO_DVFS in imx6ull evk */
states = <1300000 0x1 1400000 0x0>;
};
&cpu0 {
dc-supply = <®_gpio_dvfs>;
};
but i can't find this reg_gpio_dvfs node in kernel dts directory.
please check
imx6ull-14x14-evk.dts\dts\boot\arm\arch - linux-imx - i.MX Linux kernel
Best regards
igor
Thanks a lot, igorpadykov
You the kernel version metioned above is v4.19.35
My project use a newer kernel version v4.19.56 @ imx6ull-14x14-evk.dts\dts\boot\arm\arch - linux-imx - i.MX Linux kernel
,which do not have reg_gpio_dvfs node define in dts.
Is that mean the kernel v4.19.56 or later version do not support VDD_ARM_SOC_IN voltage select by GPIO_DVFS?
or the kernel v4.19.56 controll this GPIO_DVFS by other method?
Best Regards,
kernel v4.19.56 is not supported by nxp, please post issue
on meta-freescale@lists.yoctoproject.org | Home
Supported kernels are listed on i.MX Software and Development Tools | NXP
Best regards
igor
Hi, igorpadykov
when click the “Source Code” below,
it auto jump to Code Aurora git repositories.
How can i git pull the Linux 4.19.35_1.1.0 source code?
Can you show me the full cmd name to git pull?
please check Linux 4.19.35_1.1.0 Documentation
Best regards
igor