From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- .../devicetree/bindings/watchdog/aspeed-wdt.txt | 56 ++++++++++++++++++++++ 1 file changed, 56 insertions(+) create mode 100644 Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt (limited to 'Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt') diff --git a/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt b/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt new file mode 100644 index 000000000..c5077a1f5 --- /dev/null +++ b/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt @@ -0,0 +1,56 @@ +Aspeed Watchdog Timer + +Required properties: + - compatible: must be one of: + - "aspeed,ast2400-wdt" + - "aspeed,ast2500-wdt" + + - reg: physical base address of the controller and length of memory mapped + region + +Optional properties: + + - aspeed,reset-type = "cpu|soc|system|none" + + Reset behavior - Whenever a timeout occurs the watchdog can be programmed + to generate one of three different, mutually exclusive, types of resets. + + Type "none" can be specified to indicate that no resets are to be done. + This is useful in situations where another watchdog engine on chip is + to perform the reset. + + If 'aspeed,reset-type=' is not specfied the default is to enable system + reset. + + Reset types: + + - cpu: Reset CPU on watchdog timeout + + - soc: Reset 'System on Chip' on watchdog timeout + + - system: Reset system on watchdog timeout + + - none: No reset is performed on timeout. Assumes another watchdog + engine is responsible for this. + + - aspeed,alt-boot: If property is present then boot from alternate block. + - aspeed,external-signal: If property is present then signal is sent to + external reset counter (only WDT1 and WDT2). If not + specified no external signal is sent. + - aspeed,ext-pulse-duration: External signal pulse duration in microseconds + +Optional properties for AST2500-compatible watchdogs: + - aspeed,ext-push-pull: If aspeed,external-signal is present, set the pin's + drive type to push-pull. The default is open-drain. + - aspeed,ext-active-high: If aspeed,external-signal is present and and the pin + is configured as push-pull, then set the pulse + polarity to active-high. The default is active-low. + +Example: + + wdt1: watchdog@1e785000 { + compatible = "aspeed,ast2400-wdt"; + reg = <0x1e785000 0x1c>; + aspeed,reset-type = "system"; + aspeed,external-signal; + }; -- cgit v1.2.3