beaglebone: warning "cpu cpu0: cpu0 regulator not ready, retry" during boot

[Paolo Pisati]

SRU Justification:

    Impact: during boot, the logs are spammed with several repeated warning messages.

    Fix: apply the patches, recompile and reboot.

    Testcase: try booting with and without the patches applied and see if you can find the below warning messages in your logs.

---

From dmesg:

...
[ 2.583310] cpu cpu0: cpu0 regulator not ready, retry
[ 2.588716] platform cpufreq-cpu0.0: Driver cpufreq-cpu0 requests probe deferral
[ 2.612048] bL_switcher_halve_cpus: no CPU pairing possible
[ 2.786225] cpu cpu0: cpu0 regulator not ready, retry
[ 2.791644] platform cpufreq-cpu0.0: Driver cpufreq-cpu0 requests probe deferral
[ 2.820171] cpu cpu0: cpu0 regulator not ready, retry
[ 2.825579] platform cpufreq-cpu0.0: Driver cpufreq-cpu0 requests probe deferral
[ 2.880831] cpu cpu0: cpu0 regulator not ready, retry
[ 2.891547] platform cpufreq-cpu0.0: Driver cpufreq-cpu0 requests probe deferral
[ 2.909836] cpu cpu0: cpu0 regulator not ready, retry
[ 2.915227] platform cpufreq-cpu0.0: Driver cpufreq-cpu0 requests probe deferral
[ 7.437203] cpu cpu0: cpu0 regulator not ready, retry
[ 7.470228] platform cpufreq-cpu0.0: Driver cpufreq-cpu0 requests probe deferral
[ 8.117120] cpu cpu0: cpu0 regulator not ready, retry
[ 8.136001] platform cpufreq-cpu0.0: Driver cpufreq-cpu0 requests probe deferral
[ 8.368726] cpu cpu0: cpu0 regulator not ready, retry
[ 8.383608] platform cpufreq-cpu0.0: Driver cpufreq-cpu0 requests probe deferral
[ 8.497935] cpu cpu0: cpu0 regulator not ready, retry
[ 8.514540] platform cpufreq-cpu0.0: Driver cpufreq-cpu0 requests probe deferral
[ 8.604475] cpu cpu0: cpu0 regulator not ready, retry
[ 8.619969] platform cpufreq-cpu0.0: Driver cpufreq-cpu0 requests probe deferral
[ 9.249407] cpu cpu0: cpu0 regulator not ready, retry
[ 9.265457] platform cpufreq-cpu0.0: Driver cpufreq-cpu0 requests probe deferral
[ 9.393519] cpu cpu0: cpu0 regulator not ready, retry
[ 9.411153] platform cpufreq-cpu0.0: Driver cpufreq-cpu0 requests probe deferral
[ 9.411513] cpu cpu0: cpu0 regulator not ready, retry
[ 9.445954] platform cpufreq-cpu0.0: Driver cpufreq-cpu0 requests probe deferral
[ 9.664395] cpu cpu0: cpu0 regulator not ready, retry
[ 9.684708] platform cpufreq-cpu0.0: Driver cpufreq-cpu0 requests probe deferral
...

that's because the cpufreq-cpu0 driver (that's built-in) requires the tsp65217 regulator driver that is compiled as a module (and not available during boot).

While it's only a warning and it goes away when the rootfs is mounted (and the tps65217_regulator module is loaded), it's annoying and it spams the syslog.

[Brad Figg (brad-figg)]

This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:

apport-collect 1456987

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.