Wakeup Source Configuration iMX8QXP/DX

[jith]

How to configure wakeup source in Cortex-m4 for iMX8QXP/DX.Planning to write mem to /sys/power/state entry and make the system into low power mode. Then need to wake up the system up using interface which is handled in Cortex-M4.

Could you please provide steps to configure wake source to preform the same.

[igorpadykov]

Hi Jith

I am not aware of gpio wake examples, in general gpio wakeup

is implemented in the gpio-mxc driver, one can look at linux commits

MLK-19305-1 soc: imx: add PAD wakeup support
MLK-19305-2 gpio: mxc: add gpio PAD wakeup support
MLK-19305-3 arm64: enable gpio PAD wakeup for i.MX8 platforms   

linux-imx - i.MX Linux kernel 

linux-imx - i.MX Linux kernel 

linux-imx - i.MX Linux kernel 

Best regards
igor
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[rob_mclean]

I found this topic helpful: "How to add iMX8QXP pad GPIO wakeup"

There is a presentation attached in that describes what changes to make to the device tree.

[jith]

Hi Igor,

Could you please share wake source example with w.r.to CortexM4.

By referring IMXLUG (Rev. L4.14.62_1.0.0_beta, 11/2018 ),I could configure the debug port as wake source as below and it works fine.

echo enabled > /sys/class/tty/ttymxc0/power/wakeup 

Some of the interfaces are handled from Cortex-M4 through RTOS.(Say flexcan).I would like to configure CAN as wake source and wake the system.

As part of my experiments I have done below

Step 1 : Configuring the wake source in CAN controller (RTOS configuration)

• WAKSRC bit to 1
• SLFWAK bit to 1

Step 2 : echo mem > /sys/power/state in Linux console and made  system to low power mode.

Step 3 : send CAN data to the system

Step 4 : checking wakeup is happened or not Linux - Not waking the system.

I could see in RM that iMXQ8XP interrupt logic are handled by IRQ STEER and GIC. 

I feel Cortex M4 interrupts are routed through IRQ steer logic and somewhere.Am I missing the wake source configuration something related same?

Could you please comment and  requesting to share if documentation is available on the same topic.

Thank you

[vinothkumars]

Hi jith‌,

Will you please give your configuration. I am also struggling in wake up.

Thanks & Regards,

VinothS,

[igorpadykov]

Hi Jith

>I could see in RM that iMXQ8XP interrupt logic are handled by IRQ STEER and GIC

right, from software side it s handled by SCFW: SCFW Porting Kit

>Could you please share wake source example with w.r.to CortexM4.

>Could you please comment and  requesting to share if documentation is available on the same topic.

I am afraid such codes with w.r.to CortexM4 are not available yet, please note that

i.MX8QXP(DX) is preproduction processor and not officially supported. Also there is no

documentation on this subject. If you have project with such features suggest to

proceed with NXP Professional Services | NXP or apply to local NXP office for special support.

Best regards
igor

[JesmithaMenezes]

Hi, I am trying to enable flexcan as wakeup source at M4 core on iMX8DXL platform. May I know if this feature is supported on FreeRTOS. 

Also, could you please guide me on the same.