On 06/28/2017 05:28 PM, Christopher Bostic wrote:True, that should be documented. Will add that.
Describe device tree optional properties:
* aspeed,arm-reet - ARM CPU reset on signal
* aspeed,no-soc-reset - SOC reset on signal
* aspeed,no-sys-reset - System reset on signal
* 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@xxxxxxxxxxxxxxxxxx>
---
v3 - Invert soc and sys reset to 'no' to preserve backwards
compatibility. SOC and SYS reset will be set by default
without any optional parameters set
v2 - Add 'aspeed,' prefix to all optional properties
- Add arm-reset, soc-reset, interrupt, alt-boot properties
---
.../devicetree/bindings/watchdog/aspeed-wdt.txt | 24 ++++++++++++++++++++++
1 file changed, 24 insertions(+)
diff --git a/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt b/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt
index c5e74d7..6f18005 100644
--- a/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt
+++ b/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt
@@ -8,9 +8,33 @@ 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/not generate 6 types of signals:
+
+ - aspeed,arm-reset: If property is present then reset ARM CPU only.
+ If not specified no ARM CPU reset is done.
+
+ - aspeed,no-soc-reset: If property is present then do not reset SOC.
+ If not specified then SOC reset is done.
+
+ - aspeed,no-sys-reset: If property is present then do not reset system.
+ Typcally used in tandem with 'aspeed-external-signal'
Is this correct ? As I understand the datasheet, it could also used in tandem with
aspeed,interrupt.
As the aspeed watchdog driver exists prior to this change an SOC reset is done by
+ If not specified then system reset is done.
+
I'll leave it up to Rob to decide, but for my part I don't understand no-soc-reset.
I would instead use four properties.Per my response above I think it should remain as aspeed,no-soc-reset due to
aspeed,arm-reset
aspeed,soc-reset
aspeed,sys-reset (which is the default)Again as per our discussion yesterday I need some way to specify how system
aspeed,no-resetThis parameter seems ambiguous as we could be doing a 'no system reset'
OK, will add that.
There should also be a note explaining that the above are mutually exclusive.
+ - aspeed,interrupt: If property is present then interrupt CPU.
+ If not specified then don't interrupt CPU.
+
+ - 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.
For consistency, either add an empty line here or remove the empty lines above
+ - aspeed,alt-boot: If property is present then boot from alternate block.
+
Example:
wdt1: watchdog@1e785000 {
compatible = "aspeed,ast2400-wdt";
reg = <0x1e785000 0x1c>;
+ aspeed,no-sys-reset;
+ aspeed,external-signal;
};