i.MX ProcessorsのトピックRe: How to change LPDDR4 clock?

How to change LPDDR4 clock?

JamesShih — Fri, 23 May 2025 18:12:34 GMT

Hi,

I'm using i.MX8m-mini-bb EVK and would like to slow down the clock for LPDDR4, I tried to use the patch from the following link, but unfortunately it didn't work on my end, just wondering what is the proper way for me to either dynamically configure or fixed configure for the clock in LPDDR4?

https://patchwork.kernel.org/project/linux-clk/patch/71f9ecb1152b1860399e59aacb22c467d519b0f5.1566315740.git.leonard.crestez@nxp.com/

Thanks.

James Shih

Re: How to change LPDDR4 clock?

JosephAtNXP — Mon, 26 May 2025 18:47:12 GMT

Hi,

Thank you for your interest in NXP Semiconductor products,

Please review Linux Reference Manual Chapter 2.5.4 Dynamic Bus Frequency.

You could use Low bus frequency mode.

Or create a new one in arm64/boot/dts.

Regards

Re: How to change LPDDR4 clock?

JamesShih — Tue, 27 May 2025 23:37:17 GMT

Thanks, "BusFreq" works on my end.

But one more question is that why "DevFreq" not working on my end?
My original way is followed this patch for the control in "DevFreq", but somehow it didn't work on my end.
https://patchwork.kernel.org/project/linux-clk/patch/71f9ecb1152b1860399e59aacb22c467d519b0f5.1566315740.git.leonard.crestez@nxp.com/