Linux/PROCESSOR-SDK-AM335X: Suspend/resume issue

Nick King

Expert 1280 points

Part Number: PROCESSOR-SDK-AM335X

Tool/software: Linux

hello all

i am using latest TI SDK with beagle bone black

normally i am able to put the device in sleep mode and i am able to wake up the BBB on wake up pin

but when i use your DMtimer kernel module and if it is running then i am not able to wake up the CPU but if DMTimer is not running wake up works fine

can you please let me know the .suspend and .resume implementation to wake up the cpu

Regards

over 7 years ago

0 Pavel Botev over 7 years ago

TI__Guru**** 170625 points

Hi Nick,

Please refer to the below links regarding suspend/resume implementation:

processors.wiki.ti.com/.../Linux_Core_Power_Management_User's_Guide_(v4.4)
processors.wiki.ti.com/.../Debugging_AM335x_Suspend-Resume_Issues

www.ti.com/.../sprac74a.pdf

e2e.ti.com/.../630170
e2e.ti.com/.../599114

Regards,
Pavel

0 Nick King over 7 years ago in reply to Pavel Botev

Expert 1280 points

thanks pavel

but i think you got it wrong only when DMtimer kernel module is running we are unable to wake up if this module is not running we are able to wake up the cpu so we need some basic implemation of .suspend and .resume in the kernel module

Regards

0 Pavel Botev over 7 years ago in reply to Nick King

TI__Guru**** 170625 points

Nick King said:
only when DMtimer kernel module is running we are unable to wake up if this module is not running we are able to wake up the cpu

Yes, I understand this

Nick King said:
so we need some basic implemation of .suspend and .resume in the kernel module

I do not understand this. Please provide more details of your needs

0 Nick King over 7 years ago in reply to Pavel Botev

Expert 1280 points

thanks pavel

now please see the attached file after compile it as a kernel module and insmod in the running board and then when we put the cpu to sleep mode we are unable to wake up

this code was give by TI we did some changes and it works for us

now the only problem is we cannot wake up the cpu after we put in sleep mode.

Regards

0 Nick King over 7 years ago in reply to Pavel Botev

Expert 1280 points

any reply pavel

0 Pavel Botev over 7 years ago in reply to Nick King

TI__Guru**** 170625 points

Hi Nick,

From what I understand you need to add suspend/resume functionality in your custom driver timer_counter.c. You can take as reference other drivers like I2C, McASP, WDT, etc, and see how suspend/resume is implemented there:

linux-4.9.69/arch/arm/mach-omap2/timer.c
linux-4.9.69/drivers/rtc/rtc-omap.c
linux-4.9.69/drivers/watchdog/omap_wdt.c
linux-4.9.69/sound/soc/davinci/davinci-mcasp.c
linux-4.9.69/drivers/i2c/busses/i2c-omap.c

See also below doc:

linux-4.9.69/Documentation/power/runtime_pm.txt
linux-4.9.69/Documentation/power/devices.txt

There is also wiki for suspend/resume driver implementation. The wiki is for old kernel 2.6.37, but you can check it:

processors.wiki.ti.com/.../TI81XX_PSP_PM_SUSPEND_RESUME_User_Guide

Regards,
Pavel

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Linux/PROCESSOR-SDK-AM335X: Suspend/resume issue