Add a binding description for Realtek's watchdog timer as found on several of their MIPS-based SoCs (codenamed Otto), such as the RTL838x, RTL839x, and RTL930x series of switch SoCs. Signed-off-by: Sander Vanheule <sander@xxxxxxxxxxxxx> Reviewed-by: Rob Herring <robh@xxxxxxxxxx> Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx> --- v4: - add Guenter's Reviewed-by tag v2: - add realtek,rtl9300-wdt compatible - make interrupts property required - add Rob's Reviewed-by tag --- .../bindings/watchdog/realtek,otto-wdt.yaml | 91 +++++++++++++++++++ 1 file changed, 91 insertions(+) create mode 100644 Documentation/devicetree/bindings/watchdog/realtek,otto-wdt.yaml diff --git a/Documentation/devicetree/bindings/watchdog/realtek,otto-wdt.yaml b/Documentation/devicetree/bindings/watchdog/realtek,otto-wdt.yaml new file mode 100644 index 000000000000..11b220a5e0f6 --- /dev/null +++ b/Documentation/devicetree/bindings/watchdog/realtek,otto-wdt.yaml @@ -0,0 +1,91 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/watchdog/realtek,otto-wdt.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Realtek Otto watchdog timer + +maintainers: + - Sander Vanheule <sander@xxxxxxxxxxxxx> + +description: | + The timer has two timeout phases. Both phases have a maximum duration of 32 + prescaled clock ticks, which is ca. 43s with a bus clock of 200MHz. The + minimum duration of each phase is one tick. Each phase can trigger an + interrupt, although the phase 2 interrupt will occur with the system reset. + - Phase 1: During this phase, the WDT can be pinged to reset the timeout. + - Phase 2: Starts after phase 1 has timed out, and only serves to give the + system some time to clean up, or notify others that it's going to reset. + During this phase, pinging the WDT has no effect, and a reset is + unavoidable, unless the WDT is disabled. + +allOf: + - $ref: watchdog.yaml# + +properties: + compatible: + enum: + - realtek,rtl8380-wdt + - realtek,rtl8390-wdt + - realtek,rtl9300-wdt + + reg: + maxItems: 1 + + clocks: + maxItems: 1 + + interrupts: + items: + - description: interrupt specifier for pretimeout + - description: interrupt specifier for timeout + + interrupt-names: + items: + - const: phase1 + - const: phase2 + + realtek,reset-mode: + $ref: /schemas/types.yaml#/definitions/string + description: | + Specify how the system is reset after a timeout. Defaults to "cpu" if + left unspecified. + oneOf: + - description: Reset the entire chip + const: soc + - description: | + Reset the CPU and IPsec engine, but leave other peripherals untouched + const: cpu + - description: | + Reset the execution pointer, but don't actually reset any hardware + const: software + +required: + - compatible + - reg + - clocks + - interrupts + +unevaluatedProperties: false + +dependencies: + interrupts: [ interrupt-names ] + +examples: + - | + watchdog: watchdog@3150 { + compatible = "realtek,rtl8380-wdt"; + reg = <0x3150 0xc>; + + realtek,reset-mode = "soc"; + + clocks = <&lxbus_clock>; + timeout-sec = <20>; + + interrupt-parent = <&rtlintc>; + interrupt-names = "phase1", "phase2"; + interrupts = <19>, <18>; + }; + +... -- 2.33.1
