I'm currently using yocto 1.7 and am having some issues getting the cpu suspend/resume power feature to work.
When issuing the following two command at the command prompt:
echo +30 > /sys/class/rtc/rtc0/wakealarm
echo standby > /sys/power/state
I get the following out put:
[ 104.593519] PM: Syncing filesystems ... done.
[ 104.619884] Freezing user space processes ... (elapsed 0.01 seconds) done.
[ 104.645795] Freezing remaining freezable tasks ... (elapsed 0.01 seconds) done.
[ 104.773140] hub 2-0:1.0: port 1 nyet suspended
[ 104.834071] PM: suspend of devices complete after 167.729 msecs
[ 104.840003] PM: suspend devices took 0.170 seconds
[ 104.845402] PM: late suspend of devices complete after 0.573 msecs
[ 104.852308] PM: noirq suspend of devices complete after 0.717 msecs
[ 104.858645] Disabling non-boot CPUs ...
[ 104.863205] PM: noirq resume of devices complete after 0.330 msecs
[ 104.869970] PM: early resume of devices complete after 0.396 msecs
After this the system is locked up.
I had experienced a similar issue with yocto 1.6, but when I run a master build from last October, 2014 I get the following output:
PM: Syncing filesystems ... done.
Freezing user space processes ... (elapsed 0.01 seconds) done.
Freezing remaining freezable tasks ... (elapsed 0.01 seconds) done.
PM: suspend of devices complete after 99.514 msecs
PM: suspend devices took 0.100 seconds
PM: late suspend of devices complete after 0.433 msecs
PM: noirq suspend of devices complete after 0.565 msecs
Disabling non-boot CPUs ...
CPU1: shutdown
Enabling non-boot CPUs ...
CPU1: Booted secondary processor
CPU1 is up
PM: noirq resume of devices complete after 0.311 msecs
PM: early resume of devices complete after 0.316 msecs
mxc_sdc_fb fb.26: 1920x1080 h_sync,r,l: 44,88,148 v_sync,l,u: 5,4,36 pixclock=148500000 Hz
PM: resume of devices complete after 190.285 msecs
PM: resume devices took 0.190 seconds
Restarting tasks ... done.
This suspend/resume works.
So, it looks like the feature was working at one point on the development branch.
I can see that in the distribution that works I get a CPU1: shutdown, I don't see this in the yocto 1.7 release.
Does anyone have any ideas what might be causing this issue, or what other steps I might take to track down what might be causing what looks like a lock on shutdown?
Has any one see a similar issue? Is suspend/resume working for others on yocto 1.7?
Any help would be much appreciated.
Thanks,
Ossian
已解决! 转到解答。
Yuri,
Thank you for the suggestion.
After additional investigation it turns out the issue I was having was caused by a device tree configuration issue.
If anyone else experiences a similar issue I would suggest reviewing your regulator settings in your device tree. In particular review the "pu-supply" settings.
Regards,
Ossian
From "Linux Reference Manual" of BSP documentation :
"... refer to our script in /unit_tests/suspend_random_auto.sh
or /unit_tests/suspend_quick_auto.sh".
Have a great day,
Yuri
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Yuri,
Thank you for the suggestion.
After additional investigation it turns out the issue I was having was caused by a device tree configuration issue.
If anyone else experiences a similar issue I would suggest reviewing your regulator settings in your device tree. In particular review the "pu-supply" settings.
Regards,
Ossian