Messages in this thread | | | Subject | Re: [PATCH v2 1/2] drivers/watchdog: Add optional ASPEED device tree properties | From | Christopher Bostic <> | Date | Tue, 27 Jun 2017 16:42:24 -0500 |
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On 6/27/17 4:32 PM, Guenter Roeck wrote: > On Tue, Jun 27, 2017 at 04:17:33PM -0500, Christopher Bostic wrote: >> Describe device tree optional properties: >> >> * aspeed,arm-reet - ARM CPU reset on signal >> * aspeed,soc-reset - SOC reset on signal >> * aspeed,sys-reset - System reset on signal >> Disabling system reset may be required in situations where >> one of the other watchdog engines in the system is responsible >> for this. >> * aspeed,interrupt - Interrupt CPU on signal >> * aspeed,external-signal - Generate external signal (WDT1 and WDT2 only) >> * aspeed,alt-boot - Boot from alternate block on signal >> >> Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> >> --- >> v2 - Add 'aspeed,' prefix to all optional properties >> - Add arm-reset, soc-reset, interrupt, alt-boot properties >> --- >> .../devicetree/bindings/watchdog/aspeed-wdt.txt | 25 ++++++++++++++++++++++ >> 1 file changed, 25 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt b/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt >> index c5e74d7..555b8b4 100644 >> --- a/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt >> +++ b/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt >> @@ -8,9 +8,34 @@ Required properties: >> - reg: physical base address of the controller and length of memory mapped >> region >> >> +Optional properties: >> + Signal behavior - Whenever a timeout occurs, the watchdog can be programmed >> + to generate 6 types of signals: >> + >> + - aspeed,arm-reset: If property is present then reset ARM CPU only. >> + >> + - aspeed,soc-reset: If property is present then reset SOC. >> + >> + - aspeed,sys-reset: If property is present then reset the entire chip. >> + In cases where one of the other watchdog engines >> + in the system is responsible for system reset it >> + may be required to not specify this property. >> + >> + - aspeed,interrupt: If property is present then interrupt CPU. >> + >> + - aspeed,external-signal: If property is present then signal is sent to >> + external reset counter (only WDT1 and WDT2). >> + - aspeed,alt-boot: If property is present then boot from alternate block. >> + >> Example: >> >> wdt1: watchdog@1e785000 { >> compatible = "aspeed,ast2400-wdt"; >> reg = <0x1e785000 0x1c>; >> + aspeed,arm-reset; >> + aspeed,soc-reset; >> + aspeed,sys-reset; >> + aspeed,interrupt; >> + aspeed,external-signal; >> + aspeed,alt-boot; > Is that a bit mask or a value ? I would have thought that, > for example, a complete system reset would include the SoC reset, > and a SoC reset would include the ARM reset. Generating an > interrupt while at the same time resetting the system (or > part of it) doesn't seem to make much sense either.
No these aren't bitmasks. The example was intended to indicate what could be used. In practice only a subset of each of these properties would make any sense. How would you suggest the example be formatted to convey that? Multiple examples I suppose.
Thanks, Chris
> Guenter >
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