launch: seed system time from /data on boot (no battery RTC)

launch_openpilot.sh

@@ -11,6 +11,29 @@ echo -n "1" > /data/params/d/IsMetric
 
 
 
+# --- system time ---------------------------------------------------------------
+# This hardware has no battery-backed RTC: every boot starts at 1970, so TLS fails
+# ("certificate is not yet valid") and the model list/download cannot succeed until
+# NTP or GPS catches up. Restore the last known time from /data (persists across
+# reboots) so TLS works right away; NTP/GPS correct it to the second afterwards.
+TIME_SNAPSHOT=/data/time_snapshot
+if [ -f "$TIME_SNAPSHOT" ]; then
+  SAVED_TIME=$(cat "$TIME_SNAPSHOT" 2>/dev/null || echo 0)
+  NOW_TIME=$(date +%s)
+  # only when the clock is bogus (before 2020) and the snapshot looks sane (after 2020)
+  if [ "$NOW_TIME" -lt 1577836800 ] && [ "${SAVED_TIME:-0}" -gt 1577836800 ]; then
+    sudo date -s "@$SAVED_TIME" >/dev/null 2>&1 && echo "[time] restored from snapshot: $(date)"
+  fi
+fi
+
+# keep the snapshot fresh so the next boot starts close to the real time
+(
+  while true; do
+    date +%s > "$TIME_SNAPSHOT.tmp" 2>/dev/null && mv "$TIME_SNAPSHOT.tmp" "$TIME_SNAPSHOT" 2>/dev/null
+    sleep 300
+  done
+) &
+
 # Force device timezone to Asia/Shanghai (Beijing)
 sudo ln -sf /usr/share/zoneinfo/Asia/Shanghai /data/etc/localtime
 sudo sh -c 'echo Asia/Shanghai > /data/etc/timezone'