name : rtc-sys-time-init #!/bin/sh # Adjust system time for the following reasons: # 1) Sync system time to RTC time # - On older kernel versions, RTC modules with HCTOSYS enabled cannot sync system time with # RTC time (attribute hctosys==0) # 2) Correct driver/module system time sync to invalid time (earlier than most recent time stamp) # - Built-in/loadable RTC driver with HCTOSYS enabled may set invalid time due to .e.g # uninitialized RTC or bad battery # # If the RTC time is not valid, or cannot be set, forward the system time to most recent timestamp set -eu journal() { pri=$1 shift lvl= case "$pri" in "error") lvl="<3>" ;; "warning") lvl="<4>" ;; "debug") lvl="<7>" ;; *) lvl="<6>" ;; esac # Apply priority level to all lines printf "%s\n" "$@" | while IFS= read -r line; do printf "%s\n" "$lvl$line" done } # Expects single argument RTC device node /dev/rtc* (instance name dev-rtc* with escaping undone) dev_node=$1 # ... or a path in /sys if ! [ -c "${dev_node}" ]; then dev_node="$(udevadm info --query=property --path "${dev_node}" | sed "/^DEVNAME=/{;s///;q};d")" fi # Get systemd timestamp file created during core build clock_epoch_stamp=0 if [ -e "/usr/lib/clock-epoch" ]; then clock_epoch_stamp=$(stat -L "/usr/lib/clock-epoch" -c '%Y') else journal warning "Warning: cannot stat /usr/lib/clock-epoch" fi clock_epoch_date=$(date -d @"$clock_epoch_stamp") journal debug "core/systemd build timetamp: $clock_epoch_date" # Get systemd-timesyncd timestamp file initialized to systemd build time and updated periodically # (default 60s) and at shutdown timesync_clock_stamp=0 if [ -e "/var/lib/systemd/timesync/clock" ]; then timesync_clock_stamp="$(stat -L "/var/lib/systemd/timesync/clock" -c '%Y')" else journal warning "Warning: cannot stat /var/lib/systemd/timesync/clock (expected on first boot only)" fi timesync_clock_date=$(date -d @"$timesync_clock_stamp") journal debug "timesyncd timestamp: $timesync_clock_date" most_recent_stamp=$((clock_epoch_stamp > timesync_clock_stamp ? clock_epoch_stamp : timesync_clock_stamp)) sys_time_set_res=1 if udevadm info --attribute-walk --name="$dev_node" | grep -q 'ATTR{hctosys}=="1"'; then sys_time_set_res=0 echo "Kernel synced system time to RTC $dev_node time" else echo "Reading RTC $dev_node time..." if ! rtc_stamp=$(hwclock -r -u -f "$dev_node" 2>/dev/null); then journal error "Error: cannot read RTC $dev_node" else rtc_stamp=$(date -d "$rtc_stamp" +%s) rtc_date=$(date -d @"$rtc_stamp") echo "Successfully read RTC time: $rtc_date" if [ "$rtc_stamp" -gt "$most_recent_stamp" ]; then echo "RTC time is valid, syncing system time..." if hwclock -s --noadjfile -u -f "$dev_node" 2>/dev/null; then echo "Successfully synced system time" exit 0 else journal error "Error: cannot sync system time" fi else journal error "Error: RTC time invalid, skipping system time sync" fi fi fi # At this point either (1) the RTC module synced the system time or (2) this script failed # to sync system time. In both cases we need to ensure that system time is not behind the # most recent timestamp. now_stamp=$(date +'%s') if [ "$now_stamp" -lt "$most_recent_stamp" ]; then echo "Moving system time forward to most recent timestamp..." if date -s @"$most_recent_stamp" >/dev/null 2>&1; then echo "Successfully moved system time forward" else journal error "Error: cannot forward system time" exit 1 fi else echo "System time is ahead of most recent timestamp, skipping fixup" fi exit $sys_time_set_res