Merge git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog
* git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog: [WATCHDOG] clean-up watchdog documentation [WATCHDOG] ks8695_wdt.c - new KS8695 watchdog driver
This commit is contained in:
commit
7dfb1716d7
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@ -1,3 +1,5 @@
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|||
Last reviewed: 10/05/2007
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|
||||
Berkshire Products PC Watchdog Card
|
||||
Support for ISA Cards Revision A and C
|
||||
Documentation and Driver by Ken Hollis <kenji@bitgate.com>
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|
@ -14,8 +16,8 @@
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|||
|
||||
The Watchdog Driver will automatically find your watchdog card, and will
|
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attach a running driver for use with that card. After the watchdog
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drivers have initialized, you can then talk to the card using the PC
|
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Watchdog program, available from http://ftp.bitgate.com/pcwd/.
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drivers have initialized, you can then talk to the card using a PC
|
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Watchdog program.
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I suggest putting a "watchdog -d" before the beginning of an fsck, and
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a "watchdog -e -t 1" immediately after the end of an fsck. (Remember
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|
@ -62,5 +64,3 @@
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-- Ken Hollis
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(kenji@bitgate.com)
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(This documentation may be out of date. Check
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http://ftp.bitgate.com/pcwd/ for the absolute latest additions.)
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|
|
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@ -1,3 +1,6 @@
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Last reviewed: 10/05/2007
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The Linux Watchdog driver API.
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Copyright 2002 Christer Weingel <wingel@nano-system.com>
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@ -22,7 +25,7 @@ the system. If userspace fails (RAM error, kernel bug, whatever), the
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notifications cease to occur, and the hardware watchdog will reset the
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system (causing a reboot) after the timeout occurs.
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The Linux watchdog API is a rather AD hoc construction and different
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The Linux watchdog API is a rather ad-hoc construction and different
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drivers implement different, and sometimes incompatible, parts of it.
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This file is an attempt to document the existing usage and allow
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future driver writers to use it as a reference.
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|
@ -46,14 +49,16 @@ some of the drivers support the configuration option "Disable watchdog
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shutdown on close", CONFIG_WATCHDOG_NOWAYOUT. If it is set to Y when
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compiling the kernel, there is no way of disabling the watchdog once
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it has been started. So, if the watchdog daemon crashes, the system
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will reboot after the timeout has passed.
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will reboot after the timeout has passed. Watchdog devices also usually
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support the nowayout module parameter so that this option can be controlled
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at runtime.
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Some other drivers will not disable the watchdog, unless a specific
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magic character 'V' has been sent /dev/watchdog just before closing
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the file. If the userspace daemon closes the file without sending
|
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this special character, the driver will assume that the daemon (and
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userspace in general) died, and will stop pinging the watchdog without
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disabling it first. This will then cause a reboot.
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Drivers will not disable the watchdog, unless a specific magic character 'V'
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has been sent /dev/watchdog just before closing the file. If the userspace
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daemon closes the file without sending this special character, the driver
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will assume that the daemon (and userspace in general) died, and will stop
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pinging the watchdog without disabling it first. This will then cause a
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reboot if the watchdog is not re-opened in sufficient time.
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The ioctl API:
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|
@ -227,218 +232,3 @@ The following options are available:
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[FIXME -- better explanations]
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Implementations in the current drivers in the kernel tree:
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Here I have tried to summarize what the different drivers support and
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where they do strange things compared to the other drivers.
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acquirewdt.c -- Acquire Single Board Computer
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This driver has a hardcoded timeout of 1 minute
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Supports CONFIG_WATCHDOG_NOWAYOUT
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GETSUPPORT returns KEEPALIVEPING. GETSTATUS will return 1 if
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the device is open, 0 if not. [FIXME -- isn't this rather
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silly? To be able to use the ioctl, the device must be open
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and so GETSTATUS will always return 1].
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advantechwdt.c -- Advantech Single Board Computer
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|
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Timeout that defaults to 60 seconds, supports SETTIMEOUT.
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Supports CONFIG_WATCHDOG_NOWAYOUT
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GETSUPPORT returns WDIOF_KEEPALIVEPING and WDIOF_SETTIMEOUT.
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The GETSTATUS call returns if the device is open or not.
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[FIXME -- silliness again?]
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booke_wdt.c -- PowerPC BookE Watchdog Timer
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Timeout default varies according to frequency, supports
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SETTIMEOUT
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Watchdog cannot be turned off, CONFIG_WATCHDOG_NOWAYOUT
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does not make sense
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GETSUPPORT returns the watchdog_info struct, and
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GETSTATUS returns the supported options. GETBOOTSTATUS
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returns a 1 if the last reset was caused by the
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watchdog and a 0 otherwise. This watchdog cannot be
|
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disabled once it has been started. The wdt_period kernel
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parameter selects which bit of the time base changing
|
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from 0->1 will trigger the watchdog exception. Changing
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||||
the timeout from the ioctl calls will change the
|
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wdt_period as defined above. Finally if you would like to
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replace the default Watchdog Handler you can implement the
|
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WatchdogHandler() function in your own code.
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eurotechwdt.c -- Eurotech CPU-1220/1410
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|
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The timeout can be set using the SETTIMEOUT ioctl and defaults
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to 60 seconds.
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Also has a module parameter "ev", event type which controls
|
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what should happen on a timeout, the string "int" or anything
|
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else that causes a reboot. [FIXME -- better description]
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Supports CONFIG_WATCHDOG_NOWAYOUT
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GETSUPPORT returns CARDRESET and WDIOF_SETTIMEOUT but
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GETSTATUS is not supported and GETBOOTSTATUS just returns 0.
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i810-tco.c -- Intel 810 chipset
|
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|
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Also has support for a lot of other i8x0 stuff, but the
|
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watchdog is one of the things.
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|
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The timeout is set using the module parameter "i810_margin",
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which is in steps of 0.6 seconds where 2<i810_margin<64. The
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driver supports the SETTIMEOUT ioctl.
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|
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Supports CONFIG_WATCHDOG_NOWAYOUT.
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|
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GETSUPPORT returns WDIOF_SETTIMEOUT. The GETSTATUS call
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returns some kind of timer value which ist not compatible with
|
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the other drivers. GETBOOT status returns some kind of
|
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hardware specific boot status. [FIXME -- describe this]
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ib700wdt.c -- IB700 Single Board Computer
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Default timeout of 30 seconds and the timeout is settable
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using the SETTIMEOUT ioctl. Note that only a few timeout
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values are supported.
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Supports CONFIG_WATCHDOG_NOWAYOUT
|
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GETSUPPORT returns WDIOF_KEEPALIVEPING and WDIOF_SETTIMEOUT.
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The GETSTATUS call returns if the device is open or not.
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[FIXME -- silliness again?]
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machzwd.c -- MachZ ZF-Logic
|
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Hardcoded timeout of 10 seconds
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|
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Has a module parameter "action" that controls what happens
|
||||
when the timeout runs out which can be 0 = RESET (default),
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1 = SMI, 2 = NMI, 3 = SCI.
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|
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Supports CONFIG_WATCHDOG_NOWAYOUT and the magic character
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||||
'V' close handling.
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GETSUPPORT returns WDIOF_KEEPALIVEPING, and the GETSTATUS call
|
||||
returns if the device is open or not. [FIXME -- silliness
|
||||
again?]
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||||
|
||||
mixcomwd.c -- MixCom Watchdog
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|
||||
[FIXME -- I'm unable to tell what the timeout is]
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||||
|
||||
Supports CONFIG_WATCHDOG_NOWAYOUT
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||||
|
||||
GETSUPPORT returns WDIOF_KEEPALIVEPING, GETSTATUS returns if
|
||||
the device is opened or not [FIXME -- I'm not really sure how
|
||||
this works, there seems to be some magic connected to
|
||||
CONFIG_WATCHDOG_NOWAYOUT]
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|
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pcwd.c -- Berkshire PC Watchdog
|
||||
|
||||
Hardcoded timeout of 1.5 seconds
|
||||
|
||||
Supports CONFIG_WATCHDOG_NOWAYOUT
|
||||
|
||||
GETSUPPORT returns WDIOF_OVERHEAT|WDIOF_CARDRESET and both
|
||||
GETSTATUS and GETBOOTSTATUS return something useful.
|
||||
|
||||
The SETOPTIONS call can be used to enable and disable the card
|
||||
and to ask the driver to call panic if the system overheats.
|
||||
|
||||
sbc60xxwdt.c -- 60xx Single Board Computer
|
||||
|
||||
Hardcoded timeout of 10 seconds
|
||||
|
||||
Does not support CONFIG_WATCHDOG_NOWAYOUT, but has the magic
|
||||
character 'V' close handling.
|
||||
|
||||
No bits set in GETSUPPORT
|
||||
|
||||
scx200.c -- National SCx200 CPUs
|
||||
|
||||
Not in the kernel yet.
|
||||
|
||||
The timeout is set using a module parameter "margin" which
|
||||
defaults to 60 seconds. The timeout can also be set using
|
||||
SETTIMEOUT and read using GETTIMEOUT.
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|
||||
Supports a module parameter "nowayout" that is initialized
|
||||
with the value of CONFIG_WATCHDOG_NOWAYOUT. Also supports the
|
||||
magic character 'V' handling.
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|
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shwdt.c -- SuperH 3/4 processors
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||||
|
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[FIXME -- I'm unable to tell what the timeout is]
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||||
|
||||
Supports CONFIG_WATCHDOG_NOWAYOUT
|
||||
|
||||
GETSUPPORT returns WDIOF_KEEPALIVEPING, and the GETSTATUS call
|
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returns if the device is open or not. [FIXME -- silliness
|
||||
again?]
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||||
|
||||
softdog.c -- Software watchdog
|
||||
|
||||
The timeout is set with the module parameter "soft_margin"
|
||||
which defaults to 60 seconds, the timeout is also settable
|
||||
using the SETTIMEOUT ioctl.
|
||||
|
||||
Supports CONFIG_WATCHDOG_NOWAYOUT
|
||||
|
||||
WDIOF_SETTIMEOUT bit set in GETSUPPORT
|
||||
|
||||
w83877f_wdt.c -- W83877F Computer
|
||||
|
||||
Hardcoded timeout of 30 seconds
|
||||
|
||||
Does not support CONFIG_WATCHDOG_NOWAYOUT, but has the magic
|
||||
character 'V' close handling.
|
||||
|
||||
No bits set in GETSUPPORT
|
||||
|
||||
w83627hf_wdt.c -- w83627hf watchdog
|
||||
|
||||
Timeout that defaults to 60 seconds, supports SETTIMEOUT.
|
||||
|
||||
Supports CONFIG_WATCHDOG_NOWAYOUT
|
||||
|
||||
GETSUPPORT returns WDIOF_KEEPALIVEPING and WDIOF_SETTIMEOUT.
|
||||
The GETSTATUS call returns if the device is open or not.
|
||||
|
||||
wdt.c -- ICS WDT500/501 ISA and
|
||||
wdt_pci.c -- ICS WDT500/501 PCI
|
||||
|
||||
Default timeout of 60 seconds. The timeout is also settable
|
||||
using the SETTIMEOUT ioctl.
|
||||
|
||||
Supports CONFIG_WATCHDOG_NOWAYOUT
|
||||
|
||||
GETSUPPORT returns with bits set depending on the actual
|
||||
card. The WDT501 supports a lot of external monitoring, the
|
||||
WDT500 much less.
|
||||
|
||||
wdt285.c -- Footbridge watchdog
|
||||
|
||||
The timeout is set with the module parameter "soft_margin"
|
||||
which defaults to 60 seconds. The timeout is also settable
|
||||
using the SETTIMEOUT ioctl.
|
||||
|
||||
Does not support CONFIG_WATCHDOG_NOWAYOUT
|
||||
|
||||
WDIOF_SETTIMEOUT bit set in GETSUPPORT
|
||||
|
||||
wdt977.c -- Netwinder W83977AF chip
|
||||
|
||||
Hardcoded timeout of 3 minutes
|
||||
|
||||
Supports CONFIG_WATCHDOG_NOWAYOUT
|
||||
|
||||
Does not support any ioctls at all.
|
||||
|
||||
|
|
|
@ -1,94 +0,0 @@
|
|||
Watchdog Timer Interfaces For The Linux Operating System
|
||||
|
||||
Alan Cox <alan@lxorguk.ukuu.org.uk>
|
||||
|
||||
Custom Linux Driver And Program Development
|
||||
|
||||
|
||||
The following watchdog drivers are currently implemented:
|
||||
|
||||
ICS WDT501-P
|
||||
ICS WDT501-P (no fan tachometer)
|
||||
ICS WDT500-P
|
||||
Software Only
|
||||
SA1100 Internal Watchdog
|
||||
Berkshire Products PC Watchdog Revision A & C (by Ken Hollis)
|
||||
|
||||
|
||||
All six interfaces provide /dev/watchdog, which when open must be written
|
||||
to within a timeout or the machine will reboot. Each write delays the reboot
|
||||
time another timeout. In the case of the software watchdog the ability to
|
||||
reboot will depend on the state of the machines and interrupts. The hardware
|
||||
boards physically pull the machine down off their own onboard timers and
|
||||
will reboot from almost anything.
|
||||
|
||||
A second temperature monitoring interface is available on the WDT501P cards
|
||||
and some Berkshire cards. This provides /dev/temperature. This is the machine
|
||||
internal temperature in degrees Fahrenheit. Each read returns a single byte
|
||||
giving the temperature.
|
||||
|
||||
The third interface logs kernel messages on additional alert events.
|
||||
|
||||
Both software and hardware watchdog drivers are available in the standard
|
||||
kernel. If you are using the software watchdog, you probably also want
|
||||
to use "panic=60" as a boot argument as well.
|
||||
|
||||
The wdt card cannot be safely probed for. Instead you need to pass
|
||||
wdt=ioaddr,irq as a boot parameter - eg "wdt=0x240,11".
|
||||
|
||||
The SA1100 watchdog module can be configured with the "sa1100_margin"
|
||||
commandline argument which specifies timeout value in seconds.
|
||||
|
||||
The i810 TCO watchdog modules can be configured with the "i810_margin"
|
||||
commandline argument which specifies the counter initial value. The counter
|
||||
is decremented every 0.6 seconds and default to 50 (30 seconds). Values can
|
||||
range between 3 and 63.
|
||||
|
||||
The i810 TCO watchdog driver also implements the WDIOC_GETSTATUS and
|
||||
WDIOC_GETBOOTSTATUS ioctl()s. WDIOC_GETSTATUS returns the actual counter value
|
||||
and WDIOC_GETBOOTSTATUS returns the value of TCO2 Status Register (see Intel's
|
||||
documentation for the 82801AA and 82801AB datasheet).
|
||||
|
||||
Features
|
||||
--------
|
||||
WDT501P WDT500P Software Berkshire i810 TCO SA1100WD
|
||||
Reboot Timer X X X X X X
|
||||
External Reboot X X o o o X
|
||||
I/O Port Monitor o o o X o o
|
||||
Temperature X o o X o o
|
||||
Fan Speed X o o o o o
|
||||
Power Under X o o o o o
|
||||
Power Over X o o o o o
|
||||
Overheat X o o o o o
|
||||
|
||||
The external event interfaces on the WDT boards are not currently supported.
|
||||
Minor numbers are however allocated for it.
|
||||
|
||||
|
||||
Example Watchdog Driver: see Documentation/watchdog/src/watchdog-simple.c
|
||||
|
||||
|
||||
Contact Information
|
||||
|
||||
People keep asking about the WDT watchdog timer hardware: The phone contacts
|
||||
for Industrial Computer Source are:
|
||||
|
||||
Industrial Computer Source
|
||||
http://www.indcompsrc.com
|
||||
ICS Advent, San Diego
|
||||
6260 Sequence Dr.
|
||||
San Diego, CA 92121-4371
|
||||
Phone (858) 677-0877
|
||||
FAX: (858) 677-0895
|
||||
>
|
||||
ICS Advent Europe, UK
|
||||
Oving Road
|
||||
Chichester,
|
||||
West Sussex,
|
||||
PO19 4ET, UK
|
||||
Phone: 00.44.1243.533900
|
||||
|
||||
|
||||
and please mention Linux when enquiring.
|
||||
|
||||
For full information about the PCWD cards see the pcwd-watchdog.txt document.
|
|
@ -0,0 +1,43 @@
|
|||
Last Reviewed: 10/05/2007
|
||||
|
||||
WDT Watchdog Timer Interfaces For The Linux Operating System
|
||||
Alan Cox <alan@lxorguk.ukuu.org.uk>
|
||||
|
||||
ICS WDT501-P
|
||||
ICS WDT501-P (no fan tachometer)
|
||||
ICS WDT500-P
|
||||
|
||||
All the interfaces provide /dev/watchdog, which when open must be written
|
||||
to within a timeout or the machine will reboot. Each write delays the reboot
|
||||
time another timeout. In the case of the software watchdog the ability to
|
||||
reboot will depend on the state of the machines and interrupts. The hardware
|
||||
boards physically pull the machine down off their own onboard timers and
|
||||
will reboot from almost anything.
|
||||
|
||||
A second temperature monitoring interface is available on the WDT501P cards
|
||||
This provides /dev/temperature. This is the machine internal temperature in
|
||||
degrees Fahrenheit. Each read returns a single byte giving the temperature.
|
||||
|
||||
The third interface logs kernel messages on additional alert events.
|
||||
|
||||
The wdt card cannot be safely probed for. Instead you need to pass
|
||||
wdt=ioaddr,irq as a boot parameter - eg "wdt=0x240,11".
|
||||
|
||||
Features
|
||||
--------
|
||||
WDT501P WDT500P
|
||||
Reboot Timer X X
|
||||
External Reboot X X
|
||||
I/O Port Monitor o o
|
||||
Temperature X o
|
||||
Fan Speed X o
|
||||
Power Under X o
|
||||
Power Over X o
|
||||
Overheat X o
|
||||
|
||||
The external event interfaces on the WDT boards are not currently supported.
|
||||
Minor numbers are however allocated for it.
|
||||
|
||||
|
||||
Example Watchdog Driver: see Documentation/watchdog/src/watchdog-simple.c
|
||||
|
|
@ -115,6 +115,13 @@ config IXP4XX_WATCHDOG
|
|||
|
||||
Say N if you are unsure.
|
||||
|
||||
config KS8695_WATCHDOG
|
||||
tristate "KS8695 watchdog"
|
||||
depends on ARCH_KS8695
|
||||
help
|
||||
Watchdog timer embedded into KS8695 processor. This will reboot your
|
||||
system when the timeout is reached.
|
||||
|
||||
config S3C2410_WATCHDOG
|
||||
tristate "S3C2410 Watchdog"
|
||||
depends on ARCH_S3C2410
|
||||
|
|
|
@ -29,6 +29,7 @@ obj-$(CONFIG_21285_WATCHDOG) += wdt285.o
|
|||
obj-$(CONFIG_977_WATCHDOG) += wdt977.o
|
||||
obj-$(CONFIG_IXP2000_WATCHDOG) += ixp2000_wdt.o
|
||||
obj-$(CONFIG_IXP4XX_WATCHDOG) += ixp4xx_wdt.o
|
||||
obj-$(CONFIG_KS8695_WATCHDOG) += ks8695_wdt.o
|
||||
obj-$(CONFIG_S3C2410_WATCHDOG) += s3c2410_wdt.o
|
||||
obj-$(CONFIG_SA1100_WATCHDOG) += sa1100_wdt.o
|
||||
obj-$(CONFIG_MPCORE_WATCHDOG) += mpcore_wdt.o
|
||||
|
|
|
@ -0,0 +1,308 @@
|
|||
/*
|
||||
* Watchdog driver for Kendin/Micrel KS8695.
|
||||
*
|
||||
* (C) 2007 Andrew Victor
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License version 2 as
|
||||
* published by the Free Software Foundation.
|
||||
*/
|
||||
|
||||
#include <linux/errno.h>
|
||||
#include <linux/fs.h>
|
||||
#include <linux/init.h>
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/miscdevice.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/moduleparam.h>
|
||||
#include <linux/platform_device.h>
|
||||
#include <linux/types.h>
|
||||
#include <linux/watchdog.h>
|
||||
#include <asm/bitops.h>
|
||||
#include <asm/io.h>
|
||||
#include <asm/uaccess.h>
|
||||
#include <asm/arch/regs-timer.h>
|
||||
|
||||
|
||||
#define WDT_DEFAULT_TIME 5 /* seconds */
|
||||
#define WDT_MAX_TIME 171 /* seconds */
|
||||
|
||||
static int wdt_time = WDT_DEFAULT_TIME;
|
||||
static int nowayout = WATCHDOG_NOWAYOUT;
|
||||
|
||||
module_param(wdt_time, int, 0);
|
||||
MODULE_PARM_DESC(wdt_time, "Watchdog time in seconds. (default="__MODULE_STRING(WDT_DEFAULT_TIME) ")");
|
||||
|
||||
#ifdef CONFIG_WATCHDOG_NOWAYOUT
|
||||
module_param(nowayout, int, 0);
|
||||
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
|
||||
#endif
|
||||
|
||||
|
||||
static unsigned long ks8695wdt_busy;
|
||||
|
||||
/* ......................................................................... */
|
||||
|
||||
/*
|
||||
* Disable the watchdog.
|
||||
*/
|
||||
static void inline ks8695_wdt_stop(void)
|
||||
{
|
||||
unsigned long tmcon;
|
||||
|
||||
/* disable timer0 */
|
||||
tmcon = __raw_readl(KS8695_TMR_VA + KS8695_TMCON);
|
||||
__raw_writel(tmcon & ~TMCON_T0EN, KS8695_TMR_VA + KS8695_TMCON);
|
||||
}
|
||||
|
||||
/*
|
||||
* Enable and reset the watchdog.
|
||||
*/
|
||||
static void inline ks8695_wdt_start(void)
|
||||
{
|
||||
unsigned long tmcon;
|
||||
unsigned long tval = wdt_time * CLOCK_TICK_RATE;
|
||||
|
||||
/* disable timer0 */
|
||||
tmcon = __raw_readl(KS8695_TMR_VA + KS8695_TMCON);
|
||||
__raw_writel(tmcon & ~TMCON_T0EN, KS8695_TMR_VA + KS8695_TMCON);
|
||||
|
||||
/* program timer0 */
|
||||
__raw_writel(tval | T0TC_WATCHDOG, KS8695_TMR_VA + KS8695_T0TC);
|
||||
|
||||
/* re-enable timer0 */
|
||||
tmcon = __raw_readl(KS8695_TMR_VA + KS8695_TMCON);
|
||||
__raw_writel(tmcon | TMCON_T0EN, KS8695_TMR_VA + KS8695_TMCON);
|
||||
}
|
||||
|
||||
/*
|
||||
* Reload the watchdog timer. (ie, pat the watchdog)
|
||||
*/
|
||||
static void inline ks8695_wdt_reload(void)
|
||||
{
|
||||
unsigned long tmcon;
|
||||
|
||||
/* disable, then re-enable timer0 */
|
||||
tmcon = __raw_readl(KS8695_TMR_VA + KS8695_TMCON);
|
||||
__raw_writel(tmcon & ~TMCON_T0EN, KS8695_TMR_VA + KS8695_TMCON);
|
||||
__raw_writel(tmcon | TMCON_T0EN, KS8695_TMR_VA + KS8695_TMCON);
|
||||
}
|
||||
|
||||
/*
|
||||
* Change the watchdog time interval.
|
||||
*/
|
||||
static int ks8695_wdt_settimeout(int new_time)
|
||||
{
|
||||
/*
|
||||
* All counting occurs at SLOW_CLOCK / 128 = 0.256 Hz
|
||||
*
|
||||
* Since WDV is a 16-bit counter, the maximum period is
|
||||
* 65536 / 0.256 = 256 seconds.
|
||||
*/
|
||||
if ((new_time <= 0) || (new_time > WDT_MAX_TIME))
|
||||
return -EINVAL;
|
||||
|
||||
/* Set new watchdog time. It will be used when ks8695_wdt_start() is called. */
|
||||
wdt_time = new_time;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* ......................................................................... */
|
||||
|
||||
/*
|
||||
* Watchdog device is opened, and watchdog starts running.
|
||||
*/
|
||||
static int ks8695_wdt_open(struct inode *inode, struct file *file)
|
||||
{
|
||||
if (test_and_set_bit(0, &ks8695wdt_busy))
|
||||
return -EBUSY;
|
||||
|
||||
ks8695_wdt_start();
|
||||
return nonseekable_open(inode, file);
|
||||
}
|
||||
|
||||
/*
|
||||
* Close the watchdog device.
|
||||
* If CONFIG_WATCHDOG_NOWAYOUT is NOT defined then the watchdog is also
|
||||
* disabled.
|
||||
*/
|
||||
static int ks8695_wdt_close(struct inode *inode, struct file *file)
|
||||
{
|
||||
if (!nowayout)
|
||||
ks8695_wdt_stop(); /* Disable the watchdog when file is closed */
|
||||
|
||||
clear_bit(0, &ks8695wdt_busy);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static struct watchdog_info ks8695_wdt_info = {
|
||||
.identity = "ks8695 watchdog",
|
||||
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
|
||||
};
|
||||
|
||||
/*
|
||||
* Handle commands from user-space.
|
||||
*/
|
||||
static int ks8695_wdt_ioctl(struct inode *inode, struct file *file,
|
||||
unsigned int cmd, unsigned long arg)
|
||||
{
|
||||
void __user *argp = (void __user *)arg;
|
||||
int __user *p = argp;
|
||||
int new_value;
|
||||
|
||||
switch(cmd) {
|
||||
case WDIOC_KEEPALIVE:
|
||||
ks8695_wdt_reload(); /* pat the watchdog */
|
||||
return 0;
|
||||
|
||||
case WDIOC_GETSUPPORT:
|
||||
return copy_to_user(argp, &ks8695_wdt_info, sizeof(ks8695_wdt_info)) ? -EFAULT : 0;
|
||||
|
||||
case WDIOC_SETTIMEOUT:
|
||||
if (get_user(new_value, p))
|
||||
return -EFAULT;
|
||||
|
||||
if (ks8695_wdt_settimeout(new_value))
|
||||
return -EINVAL;
|
||||
|
||||
/* Enable new time value */
|
||||
ks8695_wdt_start();
|
||||
|
||||
/* Return current value */
|
||||
return put_user(wdt_time, p);
|
||||
|
||||
case WDIOC_GETTIMEOUT:
|
||||
return put_user(wdt_time, p);
|
||||
|
||||
case WDIOC_GETSTATUS:
|
||||
case WDIOC_GETBOOTSTATUS:
|
||||
return put_user(0, p);
|
||||
|
||||
case WDIOC_SETOPTIONS:
|
||||
if (get_user(new_value, p))
|
||||
return -EFAULT;
|
||||
|
||||
if (new_value & WDIOS_DISABLECARD)
|
||||
ks8695_wdt_stop();
|
||||
if (new_value & WDIOS_ENABLECARD)
|
||||
ks8695_wdt_start();
|
||||
return 0;
|
||||
|
||||
default:
|
||||
return -ENOTTY;
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Pat the watchdog whenever device is written to.
|
||||
*/
|
||||
static ssize_t ks8695_wdt_write(struct file *file, const char *data, size_t len, loff_t *ppos)
|
||||
{
|
||||
ks8695_wdt_reload(); /* pat the watchdog */
|
||||
return len;
|
||||
}
|
||||
|
||||
/* ......................................................................... */
|
||||
|
||||
static const struct file_operations ks8695wdt_fops = {
|
||||
.owner = THIS_MODULE,
|
||||
.llseek = no_llseek,
|
||||
.ioctl = ks8695_wdt_ioctl,
|
||||
.open = ks8695_wdt_open,
|
||||
.release = ks8695_wdt_close,
|
||||
.write = ks8695_wdt_write,
|
||||
};
|
||||
|
||||
static struct miscdevice ks8695wdt_miscdev = {
|
||||
.minor = WATCHDOG_MINOR,
|
||||
.name = "watchdog",
|
||||
.fops = &ks8695wdt_fops,
|
||||
};
|
||||
|
||||
static int __init ks8695wdt_probe(struct platform_device *pdev)
|
||||
{
|
||||
int res;
|
||||
|
||||
if (ks8695wdt_miscdev.parent)
|
||||
return -EBUSY;
|
||||
ks8695wdt_miscdev.parent = &pdev->dev;
|
||||
|
||||
res = misc_register(&ks8695wdt_miscdev);
|
||||
if (res)
|
||||
return res;
|
||||
|
||||
printk("KS8695 Watchdog Timer enabled (%d seconds%s)\n", wdt_time, nowayout ? ", nowayout" : "");
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int __exit ks8695wdt_remove(struct platform_device *pdev)
|
||||
{
|
||||
int res;
|
||||
|
||||
res = misc_deregister(&ks8695wdt_miscdev);
|
||||
if (!res)
|
||||
ks8695wdt_miscdev.parent = NULL;
|
||||
|
||||
return res;
|
||||
}
|
||||
|
||||
static void ks8695wdt_shutdown(struct platform_device *pdev)
|
||||
{
|
||||
ks8695_wdt_stop();
|
||||
}
|
||||
|
||||
#ifdef CONFIG_PM
|
||||
|
||||
static int ks8695wdt_suspend(struct platform_device *pdev, pm_message_t message)
|
||||
{
|
||||
ks8695_wdt_stop();
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int ks8695wdt_resume(struct platform_device *pdev)
|
||||
{
|
||||
if (ks8695wdt_busy)
|
||||
ks8695_wdt_start();
|
||||
return 0;
|
||||
}
|
||||
|
||||
#else
|
||||
#define ks8695wdt_suspend NULL
|
||||
#define ks8695wdt_resume NULL
|
||||
#endif
|
||||
|
||||
static struct platform_driver ks8695wdt_driver = {
|
||||
.probe = ks8695wdt_probe,
|
||||
.remove = __exit_p(ks8695wdt_remove),
|
||||
.shutdown = ks8695wdt_shutdown,
|
||||
.suspend = ks8695wdt_suspend,
|
||||
.resume = ks8695wdt_resume,
|
||||
.driver = {
|
||||
.name = "ks8695_wdt",
|
||||
.owner = THIS_MODULE,
|
||||
},
|
||||
};
|
||||
|
||||
static int __init ks8695_wdt_init(void)
|
||||
{
|
||||
/* Check that the heartbeat value is within range; if not reset to the default */
|
||||
if (ks8695_wdt_settimeout(wdt_time)) {
|
||||
ks8695_wdt_settimeout(WDT_DEFAULT_TIME);
|
||||
pr_info("ks8695_wdt: wdt_time value must be 1 <= wdt_time <= %i, using %d\n", wdt_time, WDT_MAX_TIME);
|
||||
}
|
||||
|
||||
return platform_driver_register(&ks8695wdt_driver);
|
||||
}
|
||||
|
||||
static void __exit ks8695_wdt_exit(void)
|
||||
{
|
||||
platform_driver_unregister(&ks8695wdt_driver);
|
||||
}
|
||||
|
||||
module_init(ks8695_wdt_init);
|
||||
module_exit(ks8695_wdt_exit);
|
||||
|
||||
MODULE_AUTHOR("Andrew Victor");
|
||||
MODULE_DESCRIPTION("Watchdog driver for KS8695");
|
||||
MODULE_LICENSE("GPL");
|
||||
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
|
Loading…
Reference in New Issue