[Unit]
Description=Intel CPU undervolting
After=multi-user.target suspend.target

Wants=modprobe@phc_intel.service
After=modprobe@phc_intel.service

[Service]
Type=oneshot
User=root
# wait until all cores become ready
ExecStart=sleep 1 ; /usr/bin/phc-intel start
ExecReload=/usr/bin/phc-intel stop ; /usr/bin/phc-intel start

[Install]
WantedBy=multi-user.target suspend.target