i.MX ProcessorsのトピックRe: IMX93 power management

IMX93 power management

romulus — Tue, 07 Jan 2025 02:18:46 GMT

I'm conducting power management investigations and tests on an IMX93 development board.

The IMX93 has two processors: an Arm Cortex-A55 and an Arm Cortex-M33.

Current Situation:

When I input the reboot command through the A55's serial port (USB-Enhanced-SERIAL-A-CH342), both the A55 and M33 restart.

Desired Behavior:

I want to modify this so that when I input the reboot command through the A55's serial port (USB-Enhanced-SERIAL-A-CH342), only the A55 restarts, while the M33 continues to operate normally.

Problem:

I haven't been able to locate the necessary configuration settings to achieve this.

Question:

Could you please advise on where I can modify the system to achieve this desired behavior?

Thank you very much.

Re: IMX93 power management

joanxie — Wed, 08 Jan 2025 02:03:22 GMT

normally when A core and M core go to DSM, we wake up M core and put A core in the DSM, because M core has fast response and lower power consumption, since you need wake up A core, you can refer to the AN as below

i.MX 8M Low Power Design By M Core Running In System Suspend

find the example code to wake up the A core and notify the M core in Suspend mode are added in ATF of chapter 5.5.2 Use GIR for wake-up and notification

Re: IMX93 power management

romulus — Wed, 08 Jan 2025 02:10:31 GMT

Thank you very much for your answer.

The document you provided is about the i.MX8M.

To confirm, is the handling method for the i.MX93 the same as for the i.MX8M?

Re: IMX93 power management

joanxie — Tue, 14 Jan 2025 00:27:35 GMT

for imx93, when you put imx93 M core and A core to suspend mode, you can wake up A core only, one can download imx93 SDK, find the demo named "power mode switch", then use "echo mem>/sys/power/state" to set A core to suspend mode, and use power mode switch like this to set M core to suspend mode

joanxie_0-1736814432828.png

then you can just use mouse or keyboard to wake up A core only

Re: IMX93 power management

romulus — Tue, 14 Jan 2025 01:32:21 GMT

I'll try it right away.
Thank you very much.