Bug 119341
| Summary: | Dedicated wakeirqs may not work on omaps for the first resume | ||
|---|---|---|---|
| Product: | Power Management | Reporter: | Tony Lindgren (tony) |
| Component: | Run-Time-PM | Assignee: | Rafael J. Wysocki (rjw) |
| Status: | NEW --- | ||
| Severity: | normal | CC: | nm, tony |
| Priority: | P1 | ||
| Hardware: | ARM | ||
| OS: | Linux | ||
| Kernel Version: | v4.7-rc1 and recent kernels | Subsystem: | |
| Regression: | No | Bisected commit-id: | |
Actually the above scripts wakes up just fine as it sets the off mode for suspend. It's the retention suspend mode that fails, updated test script below:
#!/bin/bash
#
# Disable autoidle to prevent system entering deeper idle states
# before the first suspend as this exposes the bug.
#
uarts=$(find /sys/class/tty/tty[SO]*/device/power/ -type d)
for uart in $uarts; do
echo -1 > $uart/autosuspend_delay_ms 2>&1
done
uarts=$(find /sys/class/tty/tty[SO]*/power/ -type d 2>/dev/null)
for uart in $uarts; do
echo enabled > $uart/wakeup 2>&1
echo auto > $uart/control 2>&1
done
#
# Unless we hit a deeper idle state via PM runtime autoidle first,
# any following suspend fails to wake up from a console UART key
# press and only wakes to the rtcwake below.
#
echo 0 > /sys/kernel/debug/pm_debug/enable_off_mode
rtcwake -m mem -s 5
echo Woke up
|
Looks like unless we hit a deeper idle state first via PM runtime, any following suspend will fail to wake to a UART keypress. Allowing the system to hit a deeper idle state first via PM runtime will fix the problem. It seems there is a state somewhere saved and restored by suspend resume cycle that gets cleared by PM runtime autoidle entering deeper idle states. This can be reproduced on at least 37xx-evm with the following script: #!/bin/bash # # Disable autoidle to prevent system entering deeper idle states # before the first suspend as this exposes the bug. # uarts=$(find /sys/class/tty/tty[SO]*/device/power/ -type d) for uart in $uarts; do echo -1 > $uart/autosuspend_delay_ms 2>&1 done uarts=$(find /sys/class/tty/tty[SO]*/power/ -type d 2>/dev/null) for uart in $uarts; do echo enabled > $uart/wakeup 2>&1 echo auto > $uart/control 2>&1 done # # Unless we hit a deeper idle state via PM runtime autoidle first, # any following suspend fails to wake up from a console UART key # press and only wakes to the rtcwake below. # echo 1 > /sys/kernel/debug/pm_debug/enable_off_mode rtcwake -m mem -s 5 echo Woke up echo 0 > /sys/kernel/debug/pm_debug/enable_off_mode