Wake up from interrupt with and without M7 running

cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

Wake up from interrupt with and without M7 running

621 Views
mirkoardinghi1
Contributor IV

Hi, i have the following problem with iMX8MPlus

when I put the system in sleep

echo mem >  /sys/power/state

I am able to wake up the system with the touchscreen interrupt  but only when the core M7 is not running.

If the M7 runs, with my application, the system doesn't woke up.

The touch interrupt is in exclusive use of A53

Labels (1)
0 Kudos
Reply
4 Replies

556 Views
mirkoardinghi1
Contributor IV

Hello,

when M7 is running the touch works correctly, the touch is on 

MX8MP_IOMUXC_I2C2_SCL__I2C2_SCL
MX8MP_IOMUXC_I2C2_SDA__I2C2_SDA 
 
port 41
 
"Is the M7 running or in sleep as well?": good question, i would like M7 always running but in AN13400.pdf I read in section 3.2.2

"In Linux, you can put the kernel into Suspend mode using the command “echo mem
> /sys/power/state”. On i.MX 8M, it puts core A53 into Stop mode. When A53
is in stop and the M core is not running, the system will enter DSM directly. It is the
standard behavior supported in the standard release." 
 
ok and this is clear, but what happen when M7 si running?
 
Thanks
0 Kudos
Reply

507 Views
AldoG
NXP TechSupport
NXP TechSupport

Hello,

Apologize for the delayed response, as stated in the App note this is actually possible but it is not possible by default, please refer to the chapter 4.3 Make the M core alive when the A core is in Suspend mode for more information.

Going back to the issue at hand, are you using an NXP EVK, right?
Could you share the device tree that you are using?

Best regards/Saludos,
Aldo.

0 Kudos
Reply

419 Views
mirkoardinghi1
Contributor IV

Hi, apologize for the delay. 

I'm using a custom board, and the M7 is runnig in DDR. I attached the dts

0 Kudos
Reply

569 Views
AldoG
NXP TechSupport
NXP TechSupport

Hello,

When you have M7 running, does the touch work correctly?
Is the M7 running or in sleep as well?
Also, how are your touch connected? is it I2C?
To which port is connected?

Best regards/Saludos,
Aldo.

0 Kudos
Reply