DragonFly On-Line Manual Pages
ICHWD(4) DragonFly Kernel Interfaces Manual ICHWD(4)
ichwd -- device driver for the Intel ICH watchdog interrupt timer
To compile this driver into the kernel, place the following line in your
kernel configuration file:
Alternatively, to load the driver as a module at boot time, place the
following line in loader.conf(5):
The ichwd driver provides watchdog(4) support for the watchdog interrupt
timer present on all Intel ICH motherboard chipsets.
The ICH WDT counts down in ticks of approximately 0.6 seconds; the exact
value depends on hardware quality and environmental factors. Supported
watchdog intervals range from 2 to 63 ticks.
Note that on some ICH-based systems, the WDT may be present but disabled,
either in hardware or by the BIOS. The ichwd driver attempts to detect
this condition and will refuse to attach if it believes the WDT is dis-
Using the Intel ICH Family Watchdog Timer (WDT), Intel Application Note
AP-725, Document Number 292273-001.
The ichwd driver first appeared in FreeBSD 5.3.
The ichwd driver was written by Wm. Daryl Hawkins <email@example.com> of
Texas A&M University and Dag-Erling Smorgrav <des@FreeBSD.org>. This
manual page was written by Dag-Erling Smorgrav <des@FreeBSD.org>.
DragonFly 5.3 May 3, 2012 DragonFly 5.3