about WFI for behavior of Secondary Core of i.MX6 Dual Lite

[yuuki]

Dear all,

I have some questions about WFI for i.MX6 Dual Lite.

When WFI is executed in Primary Core in Linux BSP, would you tell me the behavior of Secondary Core?
- Is the stack pointer for Secondary Core kept?
- Is CP15 register for L1  cache and MMC  kept?

In resume from wfi, Is it necessary for Secondary Core to be initialized?

We are looking forward to receiving your swift response.

Best Regards,
Yuuki

[Yuri]

Hello,

  Please refer to section 2.3.1 [Low Level Power Management (PM)] of i.MX_Linux_Reference_Manual.pdf in Linux doc package - how WFI is used in the BSP.

http://www.nxp.com/webapp/Download?colCode=L4.1.15_2.1.0_LINUX_DOCS&Parent_nodeId=133769948107170617... 

Summary page :

i.MX 6 / i.MX 7 Series Software and Development Tool|NXP 

  Procedures cpu_do_idle() and imx6_suspend() are involved here.

< https://github.com/torvalds/linux/blob/master/arch/arm/mach-imx/pm-imx6.c >

< https://github.com/torvalds/linux/blob/master/arch/arm/mach-imx/suspend-imx6.S >

Also, the following presentation may be helpful.

Q2.12: Idling ARMs in a busy world: Linux Power Management for ARM Mu… 

Have a great day,

Yuri

------------------------------------------------------------------------------

Note: If this post answers your question, please click the Correct Answer button. Thank you!