diff mbox series

[v6,1/3] dt-bindings: watchdog: ti,rti-wdt: Add support for WDIOF_CARDRESET

Message ID 20230718021007.1338761-2-huaqian.li@siemens.com (mailing list archive)
State Accepted
Headers show
Series Add support for WDIOF_CARDRESET on TI AM65x | expand

Commit Message

Li, Hua Qian July 18, 2023, 2:10 a.m. UTC
From: Li Hua Qian <huaqian.li@siemens.com>

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.

Signed-off-by: Li Hua Qian <huaqian.li@siemens.com>
---
 .../bindings/watchdog/ti,rti-wdt.yaml         | 28 ++++++++++++++++++-
 1 file changed, 27 insertions(+), 1 deletion(-)

Comments

Krzysztof Kozlowski July 19, 2023, 7:46 a.m. UTC | #1
On 18/07/2023 04:10, huaqian.li@siemens.com wrote:
> From: Li Hua Qian <huaqian.li@siemens.com>
> 
> 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.
> 
> Signed-off-by: Li Hua Qian <huaqian.li@siemens.com>
> ---


Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>


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Best regards,
Krzysztof
Guenter Roeck July 19, 2023, 1:39 p.m. UTC | #2
On 7/17/23 19:10, huaqian.li@siemens.com wrote:
> From: Li Hua Qian <huaqian.li@siemens.com>
> 
> 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.
> 
> Signed-off-by: Li Hua Qian <huaqian.li@siemens.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
>   .../bindings/watchdog/ti,rti-wdt.yaml         | 28 ++++++++++++++++++-
>   1 file changed, 27 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/watchdog/ti,rti-wdt.yaml b/Documentation/devicetree/bindings/watchdog/ti,rti-wdt.yaml
> index fc553211e42d..9d847e4b7278 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.
> +
>   required:
>     - compatible
>     - reg
> @@ -47,7 +61,18 @@ examples:
>       /*
>        * 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.
> +     * a 32kHz clock in this case. Add a reserved memory(optional) to keep
> +     * the watchdog reset cause persistent, which was be written in 12 bytes
> +     * starting from 0xa2200000 by RTI Watchdog Firmware, then make it
> +     * possible to get watchdog reset cause in driver.
> +     *
> +     * Reserved memory should be defined as follows:
> +     * reserved-memory {
> +     *     wdt_reset_memory_region: wdt-memory@a2200000 {
> +     *         reg = <0x00 0xa2200000 0x00 0x1000>;
> +     *         no-map;
> +     *     };
> +     * }
>        */
>       #include <dt-bindings/soc/ti,sci_pm_domain.h>
>   
> @@ -58,4 +83,5 @@ examples:
>           power-domains = <&k3_pds 252 TI_SCI_PD_EXCLUSIVE>;
>           assigned-clocks = <&k3_clks 252 1>;
>           assigned-clock-parents = <&k3_clks 252 5>;
> +        memory-region = <&wdt_reset_memory_region>;
>       };
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/watchdog/ti,rti-wdt.yaml b/Documentation/devicetree/bindings/watchdog/ti,rti-wdt.yaml
index fc553211e42d..9d847e4b7278 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.
+
 required:
   - compatible
   - reg
@@ -47,7 +61,18 @@  examples:
     /*
      * 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.
+     * a 32kHz clock in this case. Add a reserved memory(optional) to keep
+     * the watchdog reset cause persistent, which was be written in 12 bytes
+     * starting from 0xa2200000 by RTI Watchdog Firmware, then make it
+     * possible to get watchdog reset cause in driver.
+     *
+     * Reserved memory should be defined as follows:
+     * reserved-memory {
+     *     wdt_reset_memory_region: wdt-memory@a2200000 {
+     *         reg = <0x00 0xa2200000 0x00 0x1000>;
+     *         no-map;
+     *     };
+     * }
      */
     #include <dt-bindings/soc/ti,sci_pm_domain.h>
 
@@ -58,4 +83,5 @@  examples:
         power-domains = <&k3_pds 252 TI_SCI_PD_EXCLUSIVE>;
         assigned-clocks = <&k3_clks 252 1>;
         assigned-clock-parents = <&k3_clks 252 5>;
+        memory-region = <&wdt_reset_memory_region>;
     };