• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 99 subscribers
  • Views 1463 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Linux/AM3356: Complete configuration for Power Management option 'disk'

Mauricio Nunez
Prodigy 180 points
Part Number: AM3356

Tool/software: Linux

Hi,

I'm working with a custom board based on the Beaglebone Black running TI-linux-kernel v 4.9.41. I would like to know the proper configuration to use the 'disk' option under '/sys/power/state'. 

  • 0
    TI__Guru 65405 points

    Hi Mauricio,

    First find out what states are supported:
    cat /sys/power/state
    If "disk" state is not supported you should enable that option in the menuconfig:
       Power management options --->
           Hibernation (aka 'suspend to disk')
    You can find some details in the Linux kernel documentation at:
    www.kernel.org/.../basic-pm-debugging.txt
    and:
    processors.wiki.ti.com/index.php

    BR
    Tsvetolin Shulev

  • 0 in reply to Cvetolin Shulev-XID
    Prodigy 180 points

    Hi, 

    All the power management options are available. The content of '/sys/power/state' is 'freeze standby mem disk'. When I try to suspend to disk using 'echo disk > /sys/power/state' the output is :

    -sh: echo: write error: No such device

    And the output of dmesg is:

    [16325.636137] PM: Syncing filesystems ...
    [16325.641252] done.
    [16325.641329] Freezing user space processes ... (elapsed 0.002 seconds) done.
    [16325.643610] PM: Basic memory bitmaps created
    [16325.643642] PM: Preallocating image memory... done (allocated 35603 pages)
    [16325.986388] PM: Allocated 142412 kbytes in 0.34 seconds (418.85 MB/s)
    [16325.986425] Freezing remaining freezable tasks ... (elapsed 0.002 seconds) done.
    [16326.002862] PM: freeze of devices complete after 9.617 msecs
    [16326.008641] PM: late freeze of devices complete after 5.689 msecs
    [16326.015176] PM: noirq freeze of devices complete after 6.458 msecs
    [16326.015229] Disabling non-boot CPUs ...
    [16326.015270] PM: Creating hibernation image:
    [16326.015270] PM: Need to copy 35481 pages
    [16326.015270] PM: Normal pages needed: 35481 + 1024, available pages: 95066
    [16326.015270] PM: Hibernation image created (35481 pages copied)
    [16326.019984] PM: noirq thaw of devices complete after 4.537 msecs
    [16326.024731] PM: early thaw of devices complete after 4.053 msecs
    [16326.028675] Suspended for 1.450 seconds
    [16326.158560] PM: thaw of devices complete after 133.731 msecs
    [16326.162968] PM: writing image.
    [16326.163016] PM: Cannot find swap device, try swapon -a.
    [16326.163040] PM: Cannot get swap writer
    [16326.275069] PM: Basic memory bitmaps freed
    [16326.275154] Restarting tasks ... done.

    I've read the basic-pm-debugging.txt document and it doesn't mention the swap device.

    How do I configure the swap device? Do I need a partition ?

  • 0 in reply to Mauricio Nunez
    TI__Guru 65405 points

    I checked and reproduced the issue. The issue is reported to power management experts but analyzing will take some time.

    BR
    Tsvetolin Shulev