Implement IPMI support for RB_POWRECYCLE

Some BMCs support power cycling the chassis via the chassis control
command 2 subcommand 2 (ipmitool called it 'chassis power cycle').  If
the BMC supports the chassis device, register a shutdown_final handler
that sends the power cycle command if request and waits up to 10s for
it to take effect. To minimize stack strain, we preallocate a ipmi
request in the softc. At the moment, we're verbose about what we're
doing.

Sponsored by: Netflix

1 files changed, 13 insertions, 0 deletions

diff --git a/share/man/man4/ipmi.4 b/share/man/man4/ipmi.4
index ba99464f17f8..cc82cb65199f 100644
--- a/share/man/man4/ipmi.4
+++ b/share/man/man4/ipmi.4
@@ -90,6 +90,17 @@ is heavily adopted from the standard and
 .Tn Linux
 driver; however, not all features described in the
 standard are supported.
+.Pp
+The
+.Nm
+driver implements the power cycling option to
+.Xr shutdown 8
+to implement power cycling of the system.
+The motherboard's BMC must support the chassis device and the optional
+power cycle subcomand of the chassis control command as described in section 28.3
+if the IPMI standard.
+The length of time the system is off will be at least one second, but
+may be longer if the power cycle interval has been set (see section 28.9).
 .Sh IOCTLS
 Sending and receiving messages through the
 .Nm
@@ -179,6 +190,8 @@ An address supplied was invalid.
 .Sh SEE ALSO
 .Xr ioctl 2 ,
 .Xr watchdog 4 ,
+.Xr reboot 8 ,
+.Xr shutdown 8 ,
 .Xr watchdog 8 ,
 .Xr watchdogd 8 ,
 .Xr watchdog 9