Recovery time for Linux from STOP or LPSTOP3 mode

[Larry5335]

When the A5 core is in STOP mode running the Linux BSP, how long does it take before Linux will respond to new tasks? How long if using LPSTOP3 mode?

[timesyssupport · Accepted solution]

Hello Larry,

Linux can be put into a LOW POWER STOP mode on Vybrid by issuing the command 'echo -n "mem" > /sys/power/state' on a terminal. We have found that resuming from this mode typically takes 270-300ms as reported by Linux, using an NFS mounted RFS and with an SD card inserted. (The millesecond number reported by either 'early resume' or 'resume' appears to be appended by '1206', eg, 1206270 ms, but this is not correct, as that would equate to ~20 minutes, and the device comes up in less than a second).

The current Linux BSP does not have support for LPSTOPx modes. We can review the support for these modes for the next major Linux kernel update for Vybrid (scheduled for end of Q4).

Thanks,

Timesys Support

[timesyssupport]

Hello Larry,

I wanted to let you know that we are currently investigating this issue. I will let you know when we have an update available.

Thanks,

Timesys Support

[karina_valencia]

timesyssupport do you have an advance on this case?

[karina_valencia]

timesyssupport can you help on this case?