The AMD CS5536 Geode companion on the ALIX.3D3 board has an internal watchdog, beeing able to reboot the system by itself if it's hangup. To use this watchdog device, kernel support is needed. In kernel 2.6.29 you have to enable

  Device Drivers  --->
    [*] Watchdog Timer Support  --->
      [*]   Disable watchdog shutdown on close
      <*>   AMD Geode CS5535/CS5536 Watchdog

for beeing able to use the watchdog timer. The Disable watchdog shutdown on close is optional. Usually if the watchdog program terminates it tell's the kernel to disable the watchdog and the kernel does. With this option you can prevent the kernel from disabling the watchdog. Continue reading →