From: Fu Wei fu.wei@linaro.org
The sbsa-gwdt.txt documentation in devicetree/bindings/watchdog is for introducing SBSA(Server Base System Architecture) Generic Watchdog device node info into FDT.
Also add sbsa-gwdt introduction in watchdog-parameters.txt
Acked-by: Arnd Bergmann arnd@arndb.de Signed-off-by: Fu Wei fu.wei@linaro.org --- .../devicetree/bindings/watchdog/sbsa-gwdt.txt | 46 ++++++++++++++++++++++ Documentation/watchdog/watchdog-parameters.txt | 6 +++ 2 files changed, 52 insertions(+)
diff --git a/Documentation/devicetree/bindings/watchdog/sbsa-gwdt.txt b/Documentation/devicetree/bindings/watchdog/sbsa-gwdt.txt new file mode 100644 index 0000000..ad8e99a --- /dev/null +++ b/Documentation/devicetree/bindings/watchdog/sbsa-gwdt.txt @@ -0,0 +1,46 @@ +* 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 64-bit address of a register + frame and the 64-bit length of that frame; currently, two frames must be + defined, in this order: + 1: Watchdog control frame + 2: Refresh frame. + +- interrupts: At least one interrupt must be defined that will be used as + the WS0 interrupt. A WS1 interrupt definition can be provided, but is + optional. The interrupts must be defined in this order: + 1: WS0 interrupt + 2: WS1 interrupt + +Optional properties +- timeout-sec: To use a timeout value that is different from the driver + default values, use this property. If used, at least one timeout value + (in seconds) must be provided. A second optional timeout value (in + seconds) may also be provided and will be used as the pre-timeout value, + if it is given. + + There are two possible sources for driver default timeout values: + (1) the driver contains hard-coded default values, or + (2) module parameters can be given when the module is loaded + + If timeout/pretimeout values are provided when the module loads, they + will take priority. Second priority will be the timeout-sec from DTB, + and third the hard-coded driver values. + +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 = <60 30>; +}; diff --git a/Documentation/watchdog/watchdog-parameters.txt b/Documentation/watchdog/watchdog-parameters.txt index 9f9ec9f..e62c8c4 100644 --- a/Documentation/watchdog/watchdog-parameters.txt +++ b/Documentation/watchdog/watchdog-parameters.txt @@ -284,6 +284,12 @@ 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 60s) +pretimeout: Watchdog pretimeout in seconds. (default 30s) +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