On 17/07/2023 06:07, huaqian.li@xxxxxxxxxxx wrote:
> From: Li Hua Qian <huaqian.li@xxxxxxxxxxx>
>
> TI RTI (Real Time Interrupt) Watchdog doesn't support to record the
> watchdog cause. Add a reserved memory to know the last reboot was caused
> by the watchdog card. In the reserved memory, some specific info will be
> saved to indicate whether the watchdog reset was triggered in last
> boot.
>
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
> Reviewed-by: Conor Dooley <conor@xxxxxxxxxx>
> Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
What? Where did these happened? Please provide links.
> Signed-off-by: Li Hua Qian <huaqian.li@xxxxxxxxxxx>
> ---
> .../bindings/watchdog/ti,rti-wdt.yaml | 41 +++++++++++++++++++
> 1 file changed, 41 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/watchdog/ti,rti-wdt.yaml b/Documentation/devicetree/bindings/watchdog/ti,rti-wdt.yaml
> index fc553211e42d..4b66c4fcdf35 100644
> --- a/Documentation/devicetree/bindings/watchdog/ti,rti-wdt.yaml
> +++ b/Documentation/devicetree/bindings/watchdog/ti,rti-wdt.yaml
> @@ -34,6 +34,20 @@ properties:
> power-domains:
> maxItems: 1
>
> + memory-region:
> + maxItems: 1
> + description:
> + Contains the watchdog reserved memory. It is optional.
> + In the reserved memory, the specified values, which are
> + PON_REASON_SOF_NUM(0xBBBBCCCC), PON_REASON_MAGIC_NUM(0xDDDDDDDD),
> + and PON_REASON_EOF_NUM(0xCCCCBBBB), are pre-stored at the first
> + 3 * 4 bytes to tell that last boot was caused by watchdog reset.
> + Once the PON reason is captured by driver(rti_wdt.c), the driver
> + is supposed to wipe the whole memory region. Surely, if this
> + property is set, at least 12 bytes reserved memory starting from
> + specific memory address(0xa220000) should be set. More please
> + refer to Example 2.
> +
> required:
> - compatible
> - reg
> @@ -59,3 +73,30 @@ examples:
> assigned-clocks = <&k3_clks 252 1>;
> assigned-clock-parents = <&k3_clks 252 5>;
> };
> +
> + - |
> + // Example 2 (Add reserved memory for watchdog reset cause):
> + /*
> + * RTI WDT in main domain on J721e SoC. Assigned clocks are used to
> + * select the source clock for the watchdog, forcing it to tick with
> + * a 32kHz clock in this case. Add a reserved memory to keep the
> + * watchdog reset cause persistent, which was be written in 12 bytes
> + * starting from 0xa2200000 by RTI Watchdog Firmware.
> + *
> + * Reserved memory should be defined as follows:
> + * reserved-memory {
> + * wdt_reset_memory_region: wdt-memory@a2200000 {
> + * reg = <0x00 0xa2200000 0x00 0x1000>;
> + * no-map;
> + * };
> + * }
> + */
Integrate it with existing binding... there is really no need for new
example for one new property.
Best regards,
Krzysztof
