In case if DW Watchdog IP core is built with WDT_USE_FIX_TOP == false,
a custom timeout periods are used to preset the timer counter. In
this case that periods should be specified in a new "snps,watchdog-tops"
property of the DW watchdog dts node.
Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>
Cc: Alexey Malahov <Alexey.Malahov@xxxxxxxxxxxxxxxxxxxx>
Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
Cc: Paul Burton <paulburton@xxxxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxxx
---
Rob, I had to remove your Reviewed-by tag, since the patch needed
to be updated a bit (see changelog).
Changelog v2:
- Rearrange SoBs.
- Move $ref to the root level of the "snps,watchdog-tops" property
so does the constraints.
- Add default TOP values array.
- Discard the label definition from the new bindings example.
---
.../bindings/watchdog/snps,dw-wdt.yaml | 33 +++++++++++++++++++
1 file changed, 33 insertions(+)
diff --git a/Documentation/devicetree/bindings/watchdog/snps,dw-wdt.yaml b/Documentation/devicetree/bindings/watchdog/snps,dw-wdt.yaml
index 5bf6dc6377f3..cc741fb5a685 100644
--- a/Documentation/devicetree/bindings/watchdog/snps,dw-wdt.yaml
+++ b/Documentation/devicetree/bindings/watchdog/snps,dw-wdt.yaml
@@ -39,6 +39,24 @@ properties:
description: Phandle to the DW Watchdog reset lane
maxItems: 1
+ snps,watchdog-tops:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ description: |
+ DW APB Watchdog custom timer intervals - Timeout Period ranges (TOPs).
+ Each TOP is a number loaded into the watchdog counter at the moment of
+ the timer restart. The counter decrementing happens each tick of the
+ reference clock. Therefore the TOPs array is equivalent to an array of
+ the timer expiration intervals supported by the DW APB Watchdog. Note
+ DW APB Watchdog IP-core might be synthesized with fixed TOP values,
+ in which case this property is unnecessary with default TOPs utilized.
+ default: [0x0001000 0x0002000 0x0004000 0x0008000
+ 0x0010000 0x0020000 0x0040000 0x0080000
+ 0x0100000 0x0200000 0x0400000 0x0800000
+ 0x1000000 0x2000000 0x4000000 0x8000000]
+ items:
+ minItems: 16
+ maxItems: 16
+
unevaluatedProperties: false
required:
@@ -55,4 +73,19 @@ examples:
clocks = <&per_base_clk>;
resets = <&wdt_rst>;
};
+
+ - |
+ watchdog@ffd02000 {
+ compatible = "snps,dw-wdt";
+ reg = <0xffd02000 0x1000>;
+ interrupts = <0 171 4>;
+ clocks = <&per_base_clk>;
+ clock-names = "tclk";
+ snps,watchdog-tops = <0x000000FF 0x000001FF 0x000003FF
+ 0x000007FF 0x0000FFFF 0x0001FFFF
+ 0x0003FFFF 0x0007FFFF 0x000FFFFF
+ 0x001FFFFF 0x003FFFFF 0x007FFFFF
+ 0x00FFFFFF 0x01FFFFFF 0x03FFFFFF
+ 0x07FFFFFF>;
+ };
...
--
2.25.1
