i.MX6ULL の電源制御方法

[armadillo ~]# poweroff

[armadillo ~]# echo +60 > /sys/class/rtc/rtc0/wakealarm  
[armadillo ~]# poweroff  
: (省略)
[   32.428051] reboot: Power down


U-Boot 2018.03-at4 (Dec 18 2018 - 18:34:38 +0900)  

CPU:   Freescale i.MX6ULL rev1.0 at 396 MHz
Reset cause: POR
I2C:   ready
DRAM:  512 MiB
MMC:   FSL_SDHC: 0, FSL_SDHC: 1
Loading Environment from MMC... OK
In:    serial
Out:   serial
Err:   serial
Net:   FEC
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