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Diffstat (limited to 'Documentation/devicetree/bindings/watchdog/aspeed,ast2400-wdt.yaml')
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diff --git a/Documentation/devicetree/bindings/watchdog/aspeed,ast2400-wdt.yaml b/Documentation/devicetree/bindings/watchdog/aspeed,ast2400-wdt.yaml new file mode 100644 index 000000000000..be78a9865584 --- /dev/null +++ b/Documentation/devicetree/bindings/watchdog/aspeed,ast2400-wdt.yaml @@ -0,0 +1,142 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/watchdog/aspeed,ast2400-wdt.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Aspeed watchdog timer controllers + +maintainers: + - Andrew Jeffery <andrew@codeconstruct.com.au> + +properties: + compatible: + enum: + - aspeed,ast2400-wdt + - aspeed,ast2500-wdt + - aspeed,ast2600-wdt + + reg: + maxItems: 1 + + clocks: + maxItems: 1 + description: > + The clock used to drive the watchdog counter. From the AST2500 no source + other than the 1MHz clock can be selected, so the clocks property is + optional. + + aspeed,reset-type: + $ref: /schemas/types.yaml#/definitions/string + enum: + - cpu + - soc + - system + - none + default: system + description: > + The watchdog can be programmed to generate one of three different types of + reset when a timeout occcurs. + + Specifying 'cpu' will only reset the processor on a timeout event. + + Specifying 'soc' will reset a configurable subset of the SoC's controllers + on a timeout event. Controllers critical to the SoC's operation may remain + untouched. The set of SoC controllers to reset may be specified via the + aspeed,reset-mask property if the node has the aspeed,ast2500-wdt or + aspeed,ast2600-wdt compatible. + + Specifying 'system' will reset all controllers on a timeout event, as if + EXTRST had been asserted. + + Specifying 'none' will cause the timeout event to have no reset effect. + Another watchdog engine on the chip must be used for chip reset operations. + + aspeed,alt-boot: + $ref: /schemas/types.yaml#/definitions/flag + description: > + Direct the watchdog to configure the SoC to boot from the alternative boot + region if a timeout occurs. + + aspeed,external-signal: + $ref: /schemas/types.yaml#/definitions/flag + description: > + Assert the timeout event on an external signal pin associated with the + watchdog controller instance. The pin must be muxed appropriately. + + aspeed,ext-pulse-duration: + $ref: /schemas/types.yaml#/definitions/uint32 + description: > + The duration, in microseconds, of the pulse emitted on the external signal + pin. + + aspeed,ext-push-pull: + $ref: /schemas/types.yaml#/definitions/flag + description: > + If aspeed,external-signal is specified in the node, set the external + signal pin's drive type to push-pull. If aspeed,ext-push-pull is not + specified then the pin is configured as open-drain. + + aspeed,ext-active-high: + $ref: /schemas/types.yaml#/definitions/flag + description: > + If both aspeed,external-signal and aspeed,ext-push-pull are specified in + the node, set the pulse polarity to active-high. If aspeed,ext-active-high + is not specified then the pin is configured as active-low. + + aspeed,reset-mask: + $ref: /schemas/types.yaml#/definitions/uint32-array + minItems: 1 + maxItems: 2 + description: > + A bitmask indicating which peripherals will be reset if the watchdog + timer expires. On AST2500 SoCs this should be a single word defined using + the AST2500_WDT_RESET_* macros; on AST2600 SoCs this should be a two-word + array with the first word defined using the AST2600_WDT_RESET1_* macros, + and the second word defined using the AST2600_WDT_RESET2_* macros. + +required: + - compatible + - reg + +allOf: + - if: + anyOf: + - required: + - aspeed,ext-push-pull + - required: + - aspeed,ext-active-high + - required: + - aspeed,reset-mask + then: + properties: + compatible: + enum: + - aspeed,ast2500-wdt + - aspeed,ast2600-wdt + - if: + required: + - aspeed,ext-active-high + then: + required: + - aspeed,ext-push-pull + +additionalProperties: false + +examples: + - | + watchdog@1e785000 { + compatible = "aspeed,ast2400-wdt"; + reg = <0x1e785000 0x1c>; + aspeed,reset-type = "system"; + aspeed,external-signal; + }; + - | + #include <dt-bindings/watchdog/aspeed-wdt.h> + watchdog@1e785040 { + compatible = "aspeed,ast2600-wdt"; + reg = <0x1e785040 0x40>; + aspeed,reset-type = "soc"; + aspeed,reset-mask = <AST2600_WDT_RESET1_DEFAULT + (AST2600_WDT_RESET2_DEFAULT & ~AST2600_WDT_RESET2_LPC)>; + }; |