I have tried searching but there doesn't seem to be much info on PPS support.  It is a standard part of modern kernels and should be pretty consistent.   On a Pine64+ using mainline kernel (debian-stretch-next) I chose an interrupt-enabled pin (PH9) updated /boot/armbianEnv.txt with overlays=pps-gpio uart1 uart2 param_pps_pin=PH9 and rebooted.  I have a device (a GPS) with its PPS output connected to the Pi2 bus pin 13 that corresponds to PH9 and during boot this appears to be c