From 59600d045ff411da193a8b5a2999681801ecd430 Mon Sep 17 00:00:00 2001 From: Biju Das Date: Fri, 26 Oct 2018 09:55:53 +0100 Subject: dt-bindings: watchdog: renesas-wdt: Document r8a77470 support RZ/G1C (R8A77470) watchdog implementation is compatible with R-Car Gen2, therefore add relevant documentation. Signed-off-by: Biju Das Reviewed-by: Fabrizio Castro Reviewed-by: Simon Horman Reviewed-by: Rob Herring Reviewed-by: Geert Uytterhoeven Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- Documentation/devicetree/bindings/watchdog/renesas-wdt.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') 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) -- cgit v1.2.3-59-g8ed1b From d02d104ea0cefc6ed33e49832c7d70ffa5ab3a67 Mon Sep 17 00:00:00 2001 From: Jerry Hoemann Date: Mon, 4 Feb 2019 16:57:36 -0700 Subject: watchdog: Update sysfs documentation. Document the sysfs attributes: pretimeout pretimeout_available_governors pretimeout_governor Signed-off-by: Jerry Hoemann Reviewed-by: Guenter Roeck Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- Documentation/ABI/testing/sysfs-class-watchdog | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) (limited to 'Documentation') 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 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 +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 +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 +Description: + It is a read/write file. When read, the currently assigned + pretimeout governor is returned. When written, it sets + the pretimeout governor. -- cgit v1.2.3-59-g8ed1b From 9d489ad121927609d6e51df1a755707966945a53 Mon Sep 17 00:00:00 2001 From: Michael Shych Date: Sun, 24 Feb 2019 17:26:31 +0000 Subject: Documentation/watchdog: Add documentation mlx-wdt driver Add documentation with details of Mellanox watchdog driver. Signed-off-by: Michael Shych Reviewed-by: Guenter Roeck Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- Documentation/watchdog/mlx-wdt.txt | 52 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 Documentation/watchdog/mlx-wdt.txt (limited to 'Documentation') 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. -- cgit v1.2.3-59-g8ed1b