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author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-03-19 19:35:51 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-03-19 19:35:51 -0700 |
commit | 1e75a9f34a5ed5902707fb74b468356c55142b71 (patch) | |
tree | 810ff2a5e9d393242e663b321c8a80a17cebe11d /Documentation | |
parent | 1c3d770043583d99118d52cad309f586ef8e7d4a (diff) | |
parent | d1ed3ba4e3d76b4ebec239c64f990c26d7935700 (diff) | |
download | linux-stable-1e75a9f34a5ed5902707fb74b468356c55142b71.tar.gz linux-stable-1e75a9f34a5ed5902707fb74b468356c55142b71.tar.bz2 linux-stable-1e75a9f34a5ed5902707fb74b468356c55142b71.zip |
Merge git://www.linux-watchdog.org/linux-watchdog
Pull watchdog updates from Wim Van Sebroeck:
- new drivers for: NI 903x/913x watchdog driver, WinSystems EBC-C384
watchdog timer and ARM SBSA watchdog driver
- Support for NCT6102D devices
- Improvements of the generic watchdog framework (improve restart
handler, make set_timeout optional, introduce infrastructure
triggered keepalives, ...
- improvements on the pnx4008 watchdog driver
- several smaller fixes and improvements
* git://www.linux-watchdog.org/linux-watchdog: (28 commits)
watchdog: Ensure that wdd is not dereferenced if NULL
watchdog: imx2: Convert to use infrastructure triggered keepalives
watchdog: dw_wdt: Convert to use watchdog infrastructure
watchdog: Add support for minimum time between heartbeats
watchdog: Make stop function optional
watchdog: Introduce WDOG_HW_RUNNING flag
watchdog: Introduce hardware maximum heartbeat in watchdog core
watchdog: Make set_timeout function optional
arm: lpc32xx: remove restart handler
arm: lpc32xx: phy3250 remove restart hook
watchdog: pnx4008: restart: support "cmd" from userspace
watchdog: pnx4008: add support for soft reset
watchdog: pnx4008: add restart handler
watchdog: pnx4008: update logging during power-on
watchdog: tangox_wdt: test clock rate to avoid division by 0
watchdog: atlas7_wdt: test clock rate to avoid division by 0
watchdog: s3c2410_wdt: Add max and min timeout values
Watchdog: introduce ARM SBSA watchdog driver
Documentation: add sbsa-gwdt driver documentation
watchdog: Add watchdog timer support for the WinSystems EBC-C384
...
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/devicetree/bindings/watchdog/sbsa-gwdt.txt | 31 | ||||
-rw-r--r-- | Documentation/watchdog/watchdog-kernel-api.txt | 59 | ||||
-rw-r--r-- | Documentation/watchdog/watchdog-parameters.txt | 12 |
3 files changed, 90 insertions, 12 deletions
diff --git a/Documentation/devicetree/bindings/watchdog/sbsa-gwdt.txt b/Documentation/devicetree/bindings/watchdog/sbsa-gwdt.txt new file mode 100644 index 000000000000..6f2d5f91964d --- /dev/null +++ b/Documentation/devicetree/bindings/watchdog/sbsa-gwdt.txt @@ -0,0 +1,31 @@ +* SBSA (Server Base System Architecture) Generic Watchdog + +The SBSA Generic Watchdog Timer is used to force a reset of the system +after two stages of timeout have elapsed. A detailed definition of the +watchdog timer can be found in the ARM document: ARM-DEN-0029 - Server +Base System Architecture (SBSA) + +Required properties: +- compatible: Should at least contain "arm,sbsa-gwdt". + +- reg: Each entry specifies the base physical address of a register frame + and the length of that frame; currently, two frames must be defined, + in this order: + 1: Watchdog control frame; + 2: Refresh frame. + +- interrupts: Should contain the Watchdog Signal 0 (WS0) SPI (Shared + Peripheral Interrupt) number of SBSA Generic Watchdog. + +Optional properties +- timeout-sec: Watchdog timeout values (in seconds). + +Example for FVP Foundation Model v8: + +watchdog@2a440000 { + compatible = "arm,sbsa-gwdt"; + reg = <0x0 0x2a440000 0 0x1000>, + <0x0 0x2a450000 0 0x1000>; + interrupts = <0 27 4>; + timeout-sec = <30>; +}; diff --git a/Documentation/watchdog/watchdog-kernel-api.txt b/Documentation/watchdog/watchdog-kernel-api.txt index 55120a055a14..917eeeabfa5e 100644 --- a/Documentation/watchdog/watchdog-kernel-api.txt +++ b/Documentation/watchdog/watchdog-kernel-api.txt @@ -52,6 +52,8 @@ struct watchdog_device { unsigned int timeout; unsigned int min_timeout; unsigned int max_timeout; + unsigned int min_hw_heartbeat_ms; + unsigned int max_hw_heartbeat_ms; struct notifier_block reboot_nb; struct notifier_block restart_nb; void *driver_data; @@ -73,8 +75,21 @@ It contains following fields: additional information about the watchdog timer itself. (Like it's unique name) * ops: a pointer to the list of watchdog operations that the watchdog supports. * timeout: the watchdog timer's timeout value (in seconds). + This is the time after which the system will reboot if user space does + not send a heartbeat request if WDOG_ACTIVE is set. * min_timeout: the watchdog timer's minimum timeout value (in seconds). -* max_timeout: the watchdog timer's maximum timeout value (in seconds). + If set, the minimum configurable value for 'timeout'. +* max_timeout: the watchdog timer's maximum timeout value (in seconds), + as seen from userspace. If set, the maximum configurable value for + 'timeout'. Not used if max_hw_heartbeat_ms is non-zero. +* min_hw_heartbeat_ms: Minimum time between heartbeats sent to the chip, + in milli-seconds. +* max_hw_heartbeat_ms: Maximum hardware heartbeat, in milli-seconds. + If set, the infrastructure will send heartbeats to the watchdog driver + if 'timeout' is larger than max_hw_heartbeat_ms, unless WDOG_ACTIVE + is set and userspace failed to send a heartbeat for at least 'timeout' + seconds. max_hw_heartbeat_ms must be set if a driver does not implement + the stop function. * reboot_nb: notifier block that is registered for reboot notifications, for internal use only. If the driver calls watchdog_stop_on_reboot, watchdog core will stop the watchdog on such notifications. @@ -123,17 +138,20 @@ are: device. The routine needs a pointer to the watchdog timer device structure as a parameter. It returns zero on success or a negative errno code for failure. -* stop: with this routine the watchdog timer device is being stopped. - The routine needs a pointer to the watchdog timer device structure as a - parameter. It returns zero on success or a negative errno code for failure. - Some watchdog timer hardware can only be started and not be stopped. The - driver supporting this hardware needs to make sure that a start and stop - routine is being provided. This can be done by using a timer in the driver - that regularly sends a keepalive ping to the watchdog timer hardware. Not all watchdog timer hardware supports the same functionality. That's why all other routines/operations are optional. They only need to be provided if they are supported. These optional routines/operations are: +* stop: with this routine the watchdog timer device is being stopped. + The routine needs a pointer to the watchdog timer device structure as a + parameter. It returns zero on success or a negative errno code for failure. + Some watchdog timer hardware can only be started and not be stopped. A + driver supporting such hardware does not have to implement the stop routine. + If a driver has no stop function, the watchdog core will set WDOG_HW_RUNNING + and start calling the driver's keepalive pings function after the watchdog + device is closed. + If a watchdog driver does not implement the stop function, it must set + max_hw_heartbeat_ms. * ping: this is the routine that sends a keepalive ping to the watchdog timer hardware. The routine needs a pointer to the watchdog timer device structure as a @@ -153,9 +171,18 @@ they are supported. These optional routines/operations are: and -EIO for "could not write value to the watchdog". On success this routine should set the timeout value of the watchdog_device to the achieved timeout value (which may be different from the requested one - because the watchdog does not necessarily has a 1 second resolution). + because the watchdog does not necessarily have a 1 second resolution). + Drivers implementing max_hw_heartbeat_ms set the hardware watchdog heartbeat + to the minimum of timeout and max_hw_heartbeat_ms. Those drivers set the + timeout value of the watchdog_device either to the requested timeout value + (if it is larger than max_hw_heartbeat_ms), or to the achieved timeout value. (Note: the WDIOF_SETTIMEOUT needs to be set in the options field of the watchdog's info structure). + If the watchdog driver does not have to perform any action but setting the + watchdog_device.timeout, this callback can be omitted. + If set_timeout is not provided but, WDIOF_SETTIMEOUT is set, the watchdog + infrastructure updates the timeout value of the watchdog_device internally + to the requested value. * get_timeleft: this routines returns the time that's left before a reset. * restart: this routine restarts the machine. It returns 0 on success or a negative errno code for failure. @@ -169,11 +196,19 @@ The 'ref' and 'unref' operations are no longer used and deprecated. The status bits should (preferably) be set with the set_bit and clear_bit alike bit-operations. The status bits that are defined are: * WDOG_ACTIVE: this status bit indicates whether or not a watchdog timer device - is active or not. When the watchdog is active after booting, then you should - set this status bit (Note: when you register the watchdog timer device with - this bit set, then opening /dev/watchdog will skip the start operation) + is active or not from user perspective. User space is expected to send + heartbeat requests to the driver while this flag is set. * WDOG_NO_WAY_OUT: this bit stores the nowayout setting for the watchdog. If this bit is set then the watchdog timer will not be able to stop. +* WDOG_HW_RUNNING: Set by the watchdog driver if the hardware watchdog is + running. The bit must be set if the watchdog timer hardware can not be + stopped. The bit may also be set if the watchdog timer is running after + booting, before the watchdog device is opened. If set, the watchdog + infrastructure will send keepalives to the watchdog hardware while + WDOG_ACTIVE is not set. + Note: when you register the watchdog timer device with this bit set, + then opening /dev/watchdog will skip the start operation but send a keepalive + request instead. To set the WDOG_NO_WAY_OUT status bit (before registering your watchdog timer device) you can either: diff --git a/Documentation/watchdog/watchdog-parameters.txt b/Documentation/watchdog/watchdog-parameters.txt index 4e4b6f10d841..c161399a6b5c 100644 --- a/Documentation/watchdog/watchdog-parameters.txt +++ b/Documentation/watchdog/watchdog-parameters.txt @@ -200,6 +200,11 @@ mv64x60_wdt: nowayout: Watchdog cannot be stopped once started (default=kernel config parameter) ------------------------------------------------- +ni903x_wdt: +timeout: Initial watchdog timeout in seconds (0<timeout<516, default=60) +nowayout: Watchdog cannot be stopped once started + (default=kernel config parameter) +------------------------------------------------- nuc900_wdt: heartbeat: Watchdog heartbeats in seconds. (default = 15) @@ -284,6 +289,13 @@ sbc_fitpc2_wdt: margin: Watchdog margin in seconds (default 60s) nowayout: Watchdog cannot be stopped once started ------------------------------------------------- +sbsa_gwdt: +timeout: Watchdog timeout in seconds. (default 10s) +action: Watchdog action at the first stage timeout, + set to 0 to ignore, 1 to panic. (default=0) +nowayout: Watchdog cannot be stopped once started + (default=kernel config parameter) +------------------------------------------------- sc1200wdt: isapnp: When set to 0 driver ISA PnP support will be disabled (default=1) io: io port |