diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-class-watchdog | 23 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/watchdog/renesas-wdt.txt | 1 | ||||
| -rw-r--r-- | Documentation/watchdog/mlx-wdt.txt | 52 |
3 files changed, 76 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-watchdog b/Documentation/ABI/testing/sysfs-class-watchdog index 736046b33040..6317ade5ad19 100644 --- a/Documentation/ABI/testing/sysfs-class-watchdog +++ b/Documentation/ABI/testing/sysfs-class-watchdog @@ -49,3 +49,26 @@ Contact: Wim Van Sebroeck <wim@iguana.be> Description: It is a read only file. It is read to know about current value of timeout programmed. + +What: /sys/class/watchdog/watchdogn/pretimeout +Date: December 2016 +Contact: Wim Van Sebroeck <wim@iguana.be> +Description: + It is a read only file. It specifies the time in seconds before + timeout when the pretimeout interrupt is delivered. Pretimeout + is an optional feature. + +What: /sys/class/watchdog/watchdogn/pretimeout_avaialable_governors +Date: February 2017 +Contact: Wim Van Sebroeck <wim@iguana.be> +Description: + It is a read only file. It shows the pretimeout governors + available for this watchdog. + +What: /sys/class/watchdog/watchdogn/pretimeout_governor +Date: February 2017 +Contact: Wim Van Sebroeck <wim@iguana.be> +Description: + It is a read/write file. When read, the currently assigned + pretimeout governor is returned. When written, it sets + the pretimeout governor. diff --git a/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt b/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt index ef2b97b72e08..9f365c1a3399 100644 --- a/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt +++ b/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt @@ -8,6 +8,7 @@ Required properties: - "renesas,r8a7743-wdt" (RZ/G1M) - "renesas,r8a7744-wdt" (RZ/G1N) - "renesas,r8a7745-wdt" (RZ/G1E) + - "renesas,r8a77470-wdt" (RZ/G1C) - "renesas,r8a774a1-wdt" (RZ/G2M) - "renesas,r8a774c0-wdt" (RZ/G2E) - "renesas,r8a7790-wdt" (R-Car H2) diff --git a/Documentation/watchdog/mlx-wdt.txt b/Documentation/watchdog/mlx-wdt.txt new file mode 100644 index 000000000000..66eeb78505c3 --- /dev/null +++ b/Documentation/watchdog/mlx-wdt.txt @@ -0,0 +1,52 @@ + Mellanox watchdog drivers + for x86 based system switches + +This driver provides watchdog functionality for various Mellanox +Ethernet and Infiniband switch systems. + +Mellanox watchdog device is implemented in a programmable logic device. + +There are 2 types of HW watchdog implementations. + +Type 1: +Actual HW timeout can be defined as a power of 2 msec. +e.g. timeout 20 sec will be rounded up to 32768 msec. +The maximum timeout period is 32 sec (32768 msec.), +Get time-left isn't supported + +Type 2: +Actual HW timeout is defined in sec. and it's the same as +a user-defined timeout. +Maximum timeout is 255 sec. +Get time-left is supported. + +Type 1 HW watchdog implementation exist in old systems and +all new systems have type 2 HW watchdog. +Two types of HW implementation have also different register map. + +Mellanox system can have 2 watchdogs: main and auxiliary. +Main and auxiliary watchdog devices can be enabled together +on the same system. +There are several actions that can be defined in the watchdog: +system reset, start fans on full speed and increase register counter. +The last 2 actions are performed without a system reset. +Actions without reset are provided for auxiliary watchdog device, +which is optional. +Watchdog can be started during a probe, in this case it will be +pinged by watchdog core before watchdog device will be opened by +user space application. +Watchdog can be initialised in nowayout way, i.e. oncse started +it can't be stopped. + +This mlx-wdt driver supports both HW watchdog implementations. + +Watchdog driver is probed from the common mlx_platform driver. +Mlx_platform driver provides an appropriate set of registers for +Mellanox watchdog device, identity name (mlx-wdt-main or mlx-wdt-aux), +initial timeout, performed action in expiration and configuration flags. +watchdog configuration flags: nowayout and start_at_boot, hw watchdog +version - type1 or type2. +The driver checks during initialization if the previous system reset +was done by the watchdog. If yes, it makes a notification about this event. + +Access to HW registers is performed through a generic regmap interface. |