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33 .Nd device driver for watchdog timer found on Winbond Super I/O chips
35 To compile this driver into the kernel, place the following line in your
36 kernel configuration file:
37 .Bd -ragged -offset indent
41 Alternatively, to load the driver as a module at boot time, place the following
44 .Bd -literal -offset indent
52 support for the watchdog interrupt timer present on at least the following
53 Winbond Super I/O chips:
61 83627HF/F/HG/G Rev. UD-A
68 driver provides the following options as
71 .Bl -tag -width "xxxxxx"
72 .It Va dev.wbwd.0.timeout_override
73 This variable allows to program the timer to a value independent on the one
76 framework while still relying on the regular updates from e.g.
78 This is particularly useful if your system provides multiple watchdogs and
79 you want them to fire in a special sequence to trigger an NMI after a shorter
80 period than the reset timeout for example.
81 The value set must not be lower than the sleep time of
83 A value of 0 disables this feature and the timeout value provided by
86 .It Va dev.wbwd.0.debug_verbose
87 If set this sysctl will tell the driver to log its current state before and
88 after the timer reset on each invocation from
90 to the kernel message buffer for debugging.
91 .It Va dev.wbwd.0.debug
92 This read-only value gives the state of some registers on last update.
97 driver also provides further sysctl options that are hidden by default.
98 See the source code for more information.
108 driver first appeared in
112 This manual page was written by
113 .An Bjoern A. Zeeb Aq Mt bz@FreeBSD.org .